Europe: the rules a ledger must satisfy, country by country

18.1How to read this chapter

Every country section follows the same order. That way the sections can be compared down a column rather than read end to end. The order is: what the books must be and who must keep them; the annual accounts and where they are filed; VAT rates, thresholds and returns; e-invoicing status and dates; what must appear on an invoice; payments and banking; direct taxes; payroll in one paragraph; the audit file the state can demand; and anything that binds the software itself rather than the business. Each section closes with the shortest honest statement of what our ledger would have to grow.

Four warnings. Figures are September 2026, and several move every six months by law. Most late-payment interest rates in this chapter are reset on 1 January and 1 July (Switzerland’s fixed statutory rate is the exception), and every one of them is a table the software must carry, not a constant. Dates for mandates that have not yet arrived are the dates announced by the government concerned, and four of them have already slipped once. Thresholds set in euro by EU law are restated in local currency in the countries that do not use the euro, so the local-currency figure is the operative one. And where research could not confirm a figure against a primary source, it is not printed here at all, rather than printed with a hedge.

Six terms recur through the whole chapter. VAT is value-added tax, the sales tax a business adds to its invoices and passes on to the state. E-invoicing is sending an invoice as structured data a computer can read, not as paper or a PDF. A mandate is a legal deadline from which a rule becomes compulsory. Reverse charge means the buyer, not the seller, reports the VAT on a sale. An audit file is a standard export of the books that the tax office can demand. A chart of accounts is the numbered list of categories a business books its money to.

18.2The common layer: what the VAT Directive makes us model

Directive 2006/112/EC is the EU VAT Directive, the law that shapes every VAT engine in the Union. Its consequence for software is a single design rule. The tax treatment of an invoice line is not a property of the customer; it is computed. The inputs are: the type of supply (goods, service, telecommunications, land, event, transport, restaurant, hire); the country the goods leave and the country they arrive in; the customer’s status, proved by a validated VAT number; and the registrations the seller holds. From those the engine derives a treatment. The treatments are: domestic; intra-Community supply, a sale of goods to a business in another EU state; acquisition, the same sale seen from the buyer’s side; reverse charge under article 196; domestic reverse charge under article 199; distance sale through the One-Stop-Shop; export; import; exempt; small-business exempt; and margin scheme. The treatment carries the wording that must be printed and the box of the VAT return the figure lands in. A ledger that stores one tax rate per customer cannot do this.

Four mechanisms follow from it. Reverse charge posts output tax (tax on sales) and input tax (tax on purchases) in the same return, so a tax code must be able to write two lines from one invoice. An intra-Community supply is exempt only if the customer’s VAT number was valid and the sale appears in the recapitulative statement, the periodic list of sales to businesses in other EU states. So the validation result has to be stored with a timestamp, and the statement has to reconcile to the return box. The One-Stop-Shop lets a seller pay the VAT of other EU states through its home tax office; a seller enters it once its sales to consumers in other EU states pass 10,000 euro a year across the Union. It needs the standard and reduced rates of all twenty-seven states and a quarterly return grouped by country of consumption, held apart from the domestic return. And the small-business scheme, since 1 January 2025, lets a business use another country’s VAT exemption. Two conditions apply: its turnover across the whole Union stays under 100,000 euro, and its turnover in that country stays under that country’s own limit. It gets a number ending in EX and files one quarterly turnover report covering all twenty-seven states, within a month of the quarter’s end.

The invoice content rules are article 226 of the Directive, and they are the same everywhere. An invoice must show: the date; a sequential number from one or more series; both VAT numbers where relevant; names and addresses; the quantity and nature of what was sold; the date of supply when it differs from the invoice date; the taxable amount per rate; the rate; the tax; and set wording for reverse charge, exemption, self-billing (where the buyer writes the invoice), cash accounting and margin schemes (tax on the profit margin only, used for second-hand goods and travel). Two of those constraints bite in code. The tax amount must be shown in the currency of the country of taxation whatever the invoice currency. So every foreign-currency invoice carries a converted tax figure and the rate used. And the number must run in sequence within its series, so invoice numbering cannot be a field the user edits freely.

18.3The common layer: what an e-invoice is

EN 16931 is the European e-invoice standard. It is a semantic model, not a file format: a list of about a hundred and sixty business terms, the named pieces of information an invoice can carry, grouped into business groups and backed by validation rules. It is written out in one of two syntaxes, the actual XML layouts: UBL 2.1 or the UN/CEFACT Cross Industry Invoice (CII). Every national variant is a restriction of that core, called a CIUS (a core invoice usage specification, which narrows the standard but never extends it). The list of them is the list of countries: XRechnung in Germany, CIUS-PT in Portugal, NLCIUS in the Netherlands, EHF in Norway, e-SLOG in Slovenia, the Romanian and Croatian profiles, and above all Peppol BIS Billing 3.0, the CIUS used on the open network and the one to implement first. A revised EN 16931 was approved on 23 October 2025 to carry the 2030 reporting fields.

Peppol is the delivery network. An invoice travels through four corners: the sender, the sender’s access point, the receiver’s access point and the receiver. An access point is a service provider that connects a business to the network, and a directory maps each business identifier to its access point. The identifier is not the VAT number but a scheme-qualified code: a national registry number with a prefix saying which register it comes from. Examples are the Belgian enterprise number, the Norwegian or Swedish organisation number, the Dutch chamber of commerce number, the Italian tax code or VAT number, and the Finnish business identity. So a customer record needs a Peppol address field separate from its tax number. A hosted ledger does not run an access point. It integrates one, registers each tenant as a participant, and handles the message-level responses that come back, the receipts saying whether an invoice was accepted. Several countries have added a fifth corner, where the access point also reports the invoice to the tax authority: Belgium from 2028, Slovakia from 2027, Ireland from 2028, and the Netherlands under its 2030 plan.

The hybrid format deserves its own paragraph, because German-speaking Europe runs on it. ZUGFeRD, known in France as Factur-X, is a PDF/A-3 file (a long-term archive PDF that may carry attachments) with the CII XML embedded inside it. The human reads the PDF; the machine reads the attachment; and in law the XML is the invoice. The profiles matter. MINIMUM and BASIC WL carry no invoice lines and are not valid e-invoices in Germany. BASIC carries lines but only part of the standard. The EN 16931 profile, also called COMFORT, carries the full core and is the one to emit. The current version is ZUGFeRD 2.3.3, the same specification as Factur-X 1.07.3. For a ledger that already renders PDFs from templates, this is the cheapest possible entry into e-invoicing: generate the XML from the same data in the same pass and embed it.

18.4The mandate calendar

This is the table to keep. It is the reason the rest of the chapter exists, and it is the input to any decision about which country to support first. A mandate is a law that makes structured invoicing compulsory. A structured invoice is invoice data in a machine-readable layout, not a PDF or a scan. Dates are those announced by the government named. At least four have already been postponed once, and the ones after 2028 should be read as intentions.

18.5The common layer: money, and the November 2026 deadline

SEPA, the single euro payments area, is the shared rulebook under which banks move euro. It covers forty-one countries: the Union, the European Economic Area, and eleven others including Switzerland and the United Kingdom. It covers only euro. Everything in Sweden, Denmark, Norway, Poland, Czechia, Hungary and sterling Britain runs on domestic rails, with domestic file formats and domestic payment references. That is where most of the per-country work in a ledger actually is.

Three changes are in flight. Instant payments arrive within seconds at any hour. Euro-area banks had to receive them from 9 January 2025 and send them from 9 October 2025; the non-euro EU countries follow in 2027 (receive from 9 January, send from 9 July). An instant transfer may not cost more than an ordinary one, so instant is now the default rail rather than the premium one. Verification of payee arrived with the sending duty. Before a transfer is authorised, the bank checks the payee name against the account and answers match, close match, no match or cannot verify. So the exact legal name of a supplier, as the bank holds it, is a field the ledger must store and keep clean, separate from the display name. Bulk files may opt out of the check, but a file full of near-misses will be queried.

And the deadline. The 2025 SEPA rulebooks, in force from 5 October 2025, moved payment files to the 2019 versions of the ISO 20022 messages: pain.001.001.09 for credit transfers, pain.008.001.08 for direct debits, camt.053.001.08 for bank statements. They permitted three forms of address: structured, hybrid and unstructured. From 15 November 2026 the unstructured form is rejected. That date is from version 1.1 of the rulebooks; version 1.0 had said 22 November, and some bank documents still quote it. A payment file whose parties carry two free-text address lines will be refused by the bank. The consequence is not in the payment module at all. It is in the customer and vendor master record, which must be split into street, building number, postcode, town and a two-letter country code. Switzerland makes the same cut-over in the same month for its own payment standards; Norwegian, German and French bank guides all name the date. This is the item in this chapter with the nearest deadline and the widest blast radius. It is a schema change plus a data migration, not a feature.

The pattern is one mechanism with twelve parameter sets: generate a reference with a check digit per invoice, print it in the country’s form, and match incoming statement lines on it. The RMA cockpit of chapter 15 already does exactly this for the Swiss case, which is why most of the Nordic and Benelux work is smaller than it looks. Late payment is the same story. Directive 2011/7/EU sets thirty days as the default payment term, sixty by agreement, interest at the central-bank rate plus eight points, and a fixed forty euro recovery fee per late invoice. Every country then publishes its own rate twice a year and some add their own fee. One table, updated in January and July.

18.6The common layer: books, retention, and rules aimed at the software

The Accounting Directive, the EU law on annual accounts, fixes the size classes that decide which report layout a company files and whether it is audited. The thresholds were raised for financial years from 2024. A micro entity now stays under roughly 450,000 euro of assets and 900,000 of turnover; a small one under 5 and 10 million, which a country may raise to 7.5 and 15 million. What is filed, and in what format, is national. XBRL or inline XBRL, the accounts tagged so a computer can read each figure, is compulsory in the Netherlands, Denmark, Belgium, Italy, Spain, Ireland, Luxembourg and the United Kingdom, and voluntary in Finland and Sweden; a Finnish bill would make it compulsory from financial years starting in July 2027. Germany sends XBRL to both the tax office and the company register. Poland, Czechia, Slovakia and Austria file a structured XML of their own; Hungary types the figures into the register’s online forms with PDF attachments; France files a PDF; Switzerland publishes no accounts at all, and a signed PDF goes with the tax return. Retention, the years the books must be kept, runs from five in Denmark and Norway to eleven in Croatia, with ten as the common case. Germany’s recent split is the awkward exception: ten years for the books, eight for the vouchers, the documents behind each entry.

The part that concerns a software vendor directly is the set of duties that national law places on the records themselves. They differ in wording and converge in substance, and the intersection is short enough to build once.

Two countries go further and regulate the product. Portugal licenses invoicing software: the vendor applies to the tax authority, receives a certificate number, and prints it on every document beside four characters of a hash that chains each document to the previous one, so a deleted or altered invoice breaks the chain. Spain will do the same from January 2027 under Verifactu, with a SHA-256 hash chain and a QR code the tax office can verify. Denmark registers bookkeeping systems and prescribes what they must do: bank reconciliation, e-invoice send and receive, a SAF-T export, backups held inside the European Economic Area. An unregistered system may be used, but then the business must vouch for the same rules itself. Hungary requires by decree that every invoicing program can export invoice data in a specified XML by date or number range, and that the taxpayer registers which program they use. Austria and several others certify cash registers rather than ledgers. For a hosted product these are the highest barriers in Europe, and they are the reason to treat Portugal and Spain as deliberate projects rather than as translations.

18.7Switzerland, and Liechtenstein

Switzerland is the country this book has already spent three chapters approaching. On paper it is the easiest country in Europe. In practice it is the most particular. There is no EU VAT, no e-invoicing mandate, no audit file, no software certification and no public filing of accounts. In exchange there is a payment slip specified to the millimetre, which appears on every invoice in the country. There is a VAT return with its own arithmetic. And there is a bookkeeping ordinance whose demands on software are precise.

The books. The rules are in articles 957 to 963b of the Code of Obligations, the Swiss commercial law. Sole traders and partnerships keep full double-entry books (every transaction booked twice, as a debit and a credit) once turnover reaches 500,000 francs. Below that a simple record of receipts, payments and assets is enough. Every legal person, meaning every company, keeps full books whatever its size. Accounts may be kept in francs or in the currency the business mainly works in, and in any national language or English. There is no compulsory chart of accounts, the numbered list of categories a business books to. But the Schweizer Kontenrahmen KMU, the standard chart for small and medium firms, is used almost everywhere. It has nine classes and four-digit account numbers, and it maps onto the minimum balance-sheet and profit-and-loss layouts the law prescribes. Books are kept for ten years. Records touching immovable property are kept for twenty under the VAT law. A full audit is required only when a company exceeds two of three limits in two consecutive years: twenty million francs of assets, forty million of turnover and 250 employees. Below that a limited review, a lighter check by an auditor, is enough. Companies with ten or fewer full-time staff may opt out of audit entirely if all shareholders agree, and most do. Accounts are approved within six months of the year end and are not published. They go to the shareholders, the tax office and the auditor as a signed paper or electronically signed PDF. That signed document is the one artefact a database cannot replace.

The bookkeeping ordinance (GeBüV, the Geschäftsbücherverordnung) is worth reading in full. It is short, and its wording is unusually kind to software. Article 3 does not demand that records be unchangeable. It demands that they be kept “so that they cannot be changed without the change being detectable”. A posting may be reversed or corrected; it may not be silently edited or deleted. Article 9 permits ordinary changeable storage, which means any database, on four conditions. The integrity of the stored information must be technically guaranteed. The time of storage must be provably unfalsifiable. The procedures must be defined and documented. And the logs must be kept with the data. Digital signatures and time stamps are given as examples, not requirements. A journal in which each entry carries a hash of the one before it, with server timestamps and a retained audit log, satisfies it. Article 6 requires that the books can be made readable without special tools when an entitled person asks. In practice that is a PDF and CSV export of every book. Article 8 requires that access to the archive be logged, and the logs kept as long as the data. Article 10 requires regular checks of the storage, and that any migration to a new format or system be logged and the log kept. Nothing in the ordinance requires Swiss hosting, government registration or a particular file format.

VAT. The rates have been 8.1, 2.6 and 3.8 per cent since 1 January 2024. The old 7.7, 2.5 and 3.7 remain on the return for late supplies, because the rate follows the date of supply, not the invoice date. So rate validity must be dated: a 2026 invoice for a 2023 supply still carries 7.7 per cent. Registration begins at 100,000 francs of worldwide turnover. That catches a foreign supplier from its first Swiss sale, unless the Swiss buyer already accounts for the tax itself. Three accounting methods exist. The effective method deducts input tax (the VAT paid on purchases) invoice by invoice and files quarterly. The Saldosteuersatz, or net tax rate, is a flat percentage set for each trade and applied to gross turnover, with no input-tax deduction; it replaces working out the tax invoice by invoice. It is allowed up to 5,005,000 francs of turnover and 103,000 francs of tax a year, and is filed half-yearly. Since 2025 a business may hold more than two such rates, one for each activity above ten per cent of its turnover. The third method is a flat-rate variant for public bodies, schools, hospitals and associations. Cash accounting, where tax falls due when money is received rather than when the invoice is issued, is available to anyone on application. Since 2025 a business under 5,005,000 francs may also file once a year, provided its returns for the last three years were filed and paid on time. The annual return is due by the end of February. Instalments are paid during the year: three, on 30 May, 30 August and 30 November, under the effective method, or one on 30 August under the net tax rate. Filing has been online-only since 1 January 2025, through the federal ePortal. The upload format is the eCH-0217 XML file, version 2.0.0 since June 2025. There is no machine-to-machine interface. Software produces the file and the user uploads it.

The return itself is a numbered form. Total consideration, meaning everything invoiced or received, goes in box 200. Deductions go in boxes 220 to 289 and turnover per rate in 302 to 343. Bezugsteuer goes in 382 and 383; that is the reverse charge, where the buyer rather than the seller reports the tax, applied to services bought from abroad. Input tax goes in 400 and 405, corrections in 410 to 420, and the balance in 500 (to pay) or 510 (to reclaim). Box 200 must be worldwide turnover, because it also sets the radio and television levy that companies above 500,000 francs pay. Article 128 of the VAT ordinance requires two reconciliations every year: turnover as declared against turnover in the annual accounts, and input tax as declared against the input-tax accounts. Any difference is filed as a correction, in the return for the period in which the 180th day after the year end falls. If no correction has arrived 240 days after the year end, the year is deemed complete and correct. That reconciliation is a report our ledger should produce. A VAT inspector asks for it, and every Swiss fiduciary (the outside bookkeeper most small firms use) prepares one each year.

Payments. Bank files follow the Swiss Payment Standards, the Swiss profile of the ISO 20022 messages: pain.001 for sending payments, camt.053 and camt.054 for statements and booking details. With the November 2026 cut-over the standards move to pain.001.001.09 and the newer camt versions, after which the older versions stop. Several large banks are retiring the old MT940 statement format at the same time. The orange and red payment slips died on 30 September 2022. Direct debit through LSV+, the bank scheme, ends on 30 September 2028 and is being replaced by eBill Direct Debit; PostFinance’s own CH-DD scheme stays. Building for LSV+ now would be building for a corpse. eBill is the national electronic-invoice channel. The invoice is delivered inside the recipient’s online banking, to be approved with one click. It has more than four million registered users, carried about 93 million transactions in 2025 and is expected to pass a hundred million in 2026. It is reachable only through one of fifteen certified network partners, which is the integration to buy rather than build. Bank data comes through SIX bLink, the Swiss open-banking platform, or through EBICS, the corporate file-transfer standard. There is no PSD2, the EU law that forces banks to open their data, so access is contractual. Statutory default interest is five per cent under article 104 of the Code of Obligations. Thirty days is the customary payment term. Collection escalates through reminders to Betreibung, the official debt-enforcement procedure run by the cantonal collection office. A dunning module should be able to export the data for that application.

Direct taxes and payroll. Federal profit tax is 8.5 per cent of after-tax profit. Cantonal and communal tax comes on top, and the combined rate ranges from 11.66 per cent in Lucerne to 20.54 in Bern, measured in the cantonal capitals, with a Swiss average of 14.43 per cent in 2026. Dividends carry the Verrechnungssteuer, a 35 per cent withholding tax. The company deducts it from the dividend, pays it to the federal tax administration within thirty days, and the recipient reclaims it. Payroll is the most parameter-heavy part. Old-age, disability and income-loss insurance (AHV/IV/EO) costs 10.6 per cent, shared equally between employer and employee. Unemployment insurance is 2.2 per cent on salary up to 148,200 francs. The occupational pension applies a coordination deduction, a fixed slice of salary (26,460 francs in 2026) left out because the state pension already covers it, and then age-banded rates of 7, 10, 15 and 18 per cent. Add accident insurance, family allowances that vary by canton, and withholding tax on foreign employees with tariff codes from A to T, set per canton. The reporting standard is Swissdec ELM, now at version 5. It sends one XML file to the compensation office, the insurers, the pension fund, the statistical office and the cantonal tax authorities at once. Certification costs a vendor 4,500 francs a year, and it is the single thing that distinguishes a Swiss payroll product from a foreign one.

Liechtenstein shares the currency, the customs territory, the VAT law almost article for article, the QR-bill and the banking standards. It differs in five ways that matter. It has its own tax administration and portals. Profit tax is a flat 12.5 per cent with a minimum of 1,800 francs a year, and there is no withholding tax on dividends. Annual accounts must actually be filed with the justice office within twelve months of the balance-sheet date. The EU General Data Protection Regulation applies instead of the Swiss data-protection act. And payroll runs on Liechtenstein’s own social-insurance system, with its own rates.

For us: the QR-bill is chapter 15 item 2 and chapter 16 item 5, still unbuilt. The VAT return, the net-tax-rate method, the reconciliations, camt import and pain.001 export already exist in the RMA cockpit. What is missing is the QR-bill itself, the eCH-0217 upload, the exchange-rate feeds, two-factor login, and an eBill network-partner integration.

18.8Germany

Germany is the largest market in the survey, and the one where the software convention is stronger than the law. Double-entry books are required of every registered merchant. Under the tax code they are also required of anyone above 800,000 euro of turnover or 80,000 euro of profit. Below that a cash-basis income statement, receipts minus payments, is enough. The charts of accounts everyone uses are SKR03 and SKR04, published by DATEV, the tax advisers’ software house. They come with automatic accounts, which carry a fixed tax treatment, and posting keys, which tell the tax software how to treat each entry. They matter because the tax adviser expects to receive the year as a DATEV EXTF posting batch, a CSV file with a prescribed header. A German ledger that cannot write that file is not a German ledger, whatever else it does.

GoBD is the German expression of the record rules: the finance ministry’s principles for keeping books electronically. It was amended in March 2024 and again in July 2025. It demands timely recording. It demands immutability, with Festschreibung, the step that locks entries so they can no longer be edited. Entries must be locked by the time the VAT return for their period is filed; until then they count only as proposals. Corrections are made by reversal, not by editing. It demands a complete change history, gap-free numbering, and a written Verfahrensdokumentation, a description of the system and the procedures around it. Retention was split by the fourth deregulation act, in force from 1 January 2025: ten years for books and annual accounts, eight years for vouchers and invoices, six for business correspondence. The audit export is the GoBD description standard, formerly called GDPdU, a folder of tables with an index file that describes them. Cash businesses additionally need a certified technical security device (TSE) in the till, the DSFinV-K export of till data, and, since 2025, registration of every till with the tax office.

VAT is 19 and 7 per cent. Restaurant food returned to 7 per cent permanently from 1 January 2026; drinks stay at 19. The small-business exemption was rebuilt in 2025. It applies when turnover was at most 25,000 euro in the previous year and stays at most 100,000 euro in the current one. Advance returns are monthly when the previous year’s VAT exceeded 9,000 euro, quarterly between 2,000 and 9,000, and not required below 2,000. A permanent one-month filing extension is available; monthly filers pay a deposit of one eleventh of the previous year’s advance payments for it. Filing is through ELSTER, the tax portal, and its ERiC library, a piece of code a vendor embeds to file directly. The domestic reverse charge, where the buyer rather than the seller reports the tax, applies under paragraph 13b to construction work for a customer that itself does construction, to scrap, to mobile phones and tablets from 5,000 euro an order, and more. Construction payments additionally suffer a 15 per cent withholding unless the supplier produces an exemption certificate. Cash accounting is available up to 800,000 euro of turnover.

E-invoicing has the clearest timetable in Europe. Since 1 January 2025 every German business must be able to receive a structured invoice, meaning an XML file a machine can read; a PDF no longer counts as one. From 1 January 2027 businesses whose 2026 turnover exceeded 800,000 euro must issue them for sales to other German businesses. From 1 January 2028 all must. The formats are XRechnung, currently version 3.0.2, and ZUGFeRD, a PDF with the XML embedded inside it. ZUGFeRD is accepted from version 2.0.1 in its EN 16931 profile (EN 16931 is the European standard invoice data set) and is now at release 2.5. There is no platform: an e-mail attachment is a legal delivery. That makes Germany the cheapest mandate to satisfy and the easiest to underestimate, because the duty to receive and process means parsing inbound XML into a payable. Public-sector invoices need a routing identifier, the Leitweg-ID, and go through the federal portal or Peppol, the European invoice-exchange network.

Money and tax. EBICS, the corporate bank file-transfer standard, is now at version 3.0.1. FinTS, the older home-banking protocol, survives for small businesses. Aggregators such as finAPI and Tink, services that fetch bank data by API, cover the rest. The camt.053 statement replaces MT940, which ceased to be a banking-industry standard in November 2025. The EPC QR code, called GiroCode, goes on the invoice by custom rather than by law; a banking app scans it to prefill the transfer. Default interest between businesses is the base rate plus nine points, reset each January and July. The base rate is 1.52 per cent from 1 July 2026, so 10.52 in all, and a forty-euro fee is added. Corporation tax is 15 per cent plus the solidarity surcharge of 5.5 per cent of the tax, 15.825 per cent together, with a legislated path down by one point a year from 2028 to 10 per cent in 2032. Trade tax, a municipal tax on business profit, comes on top at a multiplier each municipality sets. The annual accounts go to the tax office as the E-Bilanz, an XBRL file (a tagged, machine-readable financial statement), and to the company register for publication. Payroll runs on ELStAM, the database that supplies each employee’s tax features, and on the social-insurance reporting procedure for contributions. Both are certified-software territory.

For us: the DATEV export and the E-Bilanz are the two artefacts a German accountant asks for first, and we have neither. XRechnung and ZUGFeRD are the cheapest possible first e-invoicing implementation because they need no network. GoBD is satisfied by the same append-only journal and audit log that Swiss GeBüV needs.

18.9Austria

Austria reads at first like a smaller Germany and then diverges in ways that cost real work. The bookkeeping duty comes from the commercial code. Every limited company (GmbH, FlexKapG, AG) keeps double-entry books whatever its size. Sole traders and partnerships must once turnover passes 700,000 euro in two consecutive years; the duty then starts after a buffer year. If turnover overshoots by more than 300,000 euro in a single year, the duty starts from the next financial year with no buffer. A rise of the threshold to one million euro was announced in April 2026 but had not become law by September 2026. Below the threshold a cash-basis statement, receipts minus payments, is enough. The chart of accounts everyone uses is the Einheitskontenrahmen, the uniform chart: ten classes, maintained by the chamber of tax advisers and auditors. The finance ministry publishes a mapping from it to the audit file, the standard data export an inspector loads into audit software. That mapping is what an inspector expects an export to be keyed to.

Two provisions bear directly on software. Paragraph 190 of the commercial code says an entry may not be altered in a way that leaves the original content undeterminable, nor in a way that leaves doubt whether it was made originally or later. That is the same immutability duty as Germany and Switzerland, in different words. And a new provision, for financial years beginning after 31 March 2025, requires that the date of preparation of the annual accounts and the exact version prepared be documented. That is a versioning duty on the accounting system itself. Retention is seven years, and up to 22 years for documents about land and buildings. Cash businesses fall under the cash-register security regulation, the RKSV. It requires a data log in which each receipt is signed and chained to the one before, a duty to hand every cash customer a receipt, and registration of the till through the tax portal.

VAT has become the most complicated rate table in this chapter. The standard rate is 20 per cent, with 13 and 10 below it, and 19 in the two enclaves of Jungholz and Mittelberg. From 1 July 2026 there is a new 4.9 per cent rate on twelve groups of basic foodstuffs: milk, yoghurt, butter, eggs, fresh and frozen vegetables, fruit, rice, wheat flour, plain pasta, bread and table salt, each defined by customs code. It applies only where the supply consists exclusively of goods in those groups; processed foods and restaurant meals stay at 10 or 20. That is five positive rates, one of them condition-dependent. The small-business exemption, under which a firm charges no VAT and deducts none, sits at 55,000 euro with a ten per cent tolerance band, and opting out binds for five years. Cash accounting, where tax falls due when payment is received, is the compulsory default for the liberal professions and for traders below 110,000 euro of turnover; the invoice-date method is available only on application. That reverses the usual default. The reverse charge, where the buyer rather than the seller reports the tax, covers construction, scrap, emission certificates, and mobile phones, laptops, tablets, consoles and raw metals including gold and silver from 5,000 euro of net invoice value. That is a per-invoice threshold the ledger must test, not a per-customer flag.

The advance return is filed by the fifteenth of the second month following the period, monthly if prior-year turnover passed 100,000 euro and quarterly otherwise. Payment falls due the same day. Filing must be electronic, through FinanzOnline, the tax portal. The annual return is due on 30 April, or 30 June when filed electronically. Where a professional representative is engaged, the profession-wide quota arrangement extends it to 31 March of the second following year, and the tax office may extend that to 30 June. That is why an Austrian ledger is judged by what it hands the tax adviser rather than by what it files. The recapitulative statement, the list of sales to VAT-registered customers in other EU countries, is due by the end of the following month and is not filed at all when there is nothing to report.

E-invoicing to the federal government has been compulsory since 1 January 2014. A PDF by e-mail is treated as not submitted. Only the federal level compels it; regions and municipalities accept but do not require. The platform, e-Rechnung.gv.at, is reached through the business service portal (USP) or over Peppol. It accepts ebInterface, the Austrian XML invoice format, of which version 6.1 is current and versions from 5.0 cover the European standard EN 16931. It also accepts UBL, the international invoice XML, under Peppol BIS Billing 3.0, and the Cross Industry Invoice; over Peppol only UBL travels. Two Austrian fields cause most rejections. The first is an order reference that routes the invoice inside the federal system; when it is a ten-digit purchase-order number, every invoice line must also carry the matching order position number. The second is a supplier number that keys the vendor master record. There is no business-to-business mandate and none scheduled. An electronic invoice still needs the recipient’s agreement, and the horizon is the European rule of 2030. The practical advice writes itself: emit ebInterface 6.1 and Peppol UBL, and the country is covered today and in 2030.

Tax and payroll. Corporation tax is a flat 23 per cent since 2024. A minimum tax is payable even in a loss year, 500 euro for a GmbH and 3,500 for an AG, and it is credited against future tax indefinitely. Advance payments fall quarterly, on 15 February, 15 May, 15 August and 15 November. A municipal tax of 3 per cent on wages is paid over to the municipality. Dividends carry 27.5 per cent withholding. An investment allowance, reintroduced in 2023, is an extra deduction that sits alongside depreciation without reducing its base. It was temporarily doubled from 10 to 20 per cent for investments from November 2025 to the end of 2026. Payroll reporting runs through ELDA, the social-insurance data channel. A monthly contribution-basis message per employee is due by the fifteenth of the following month, and the annual wage statement by the end of February. The item a foreign ledger always misses is the Jahressechstel, the “sixth of the year”. The thirteenth and fourteenth salaries and similar payments get reduced tax rates, but only up to one sixth of the annualised regular pay. Within that sixth the first 620 euro is tax-free, the next 24,380 is taxed at six per cent, and the bands above at 27 and 35.75 per cent. If the sixth is at most 2,615 euro the concession does not apply at all and the ordinary tariff is used instead. Anything above the sixth is taxed as ordinary pay, and a year-end recalculation is needed to hold the cap. That is a payroll calculation with no equivalent anywhere else in this chapter.

Two changes in 2026 catch anyone who built earlier. From 1 January 2026 the tax portal is no longer a permitted channel to the commercial-register court. Annual accounts now go through the justice system as a defined XML structure, JAb 4.0, within nine months of the balance-sheet date. And on 2 June 2026 the ministry switched off the E-Bilanz XML upload of accounts to the tax office, which now takes a PDF until a successor exists. Intrastat, the statistical report on goods traded with other EU countries, has higher thresholds for the 2026 reporting year: five million euro on arrivals and 1.2 million on dispatches.

Three smaller things. A Kleinbetragsrechnung, a small-amount invoice with fewer required details, is allowed up to 400 euro including VAT, and the recipient’s VAT number must appear on invoices above 10,000 euro. Late payment between businesses carries the base rate plus 9.2 points, the widest margin in this chapter, plus the forty-euro compensation. And there is an Austrian audit file, SAF-T version 1.01, the OECD standard audit XML, with a published mapping from the standard chart. But it is admissible rather than compulsory. What an inspector actually asks for is an export under paragraphs 131 and 132 of the tax code, a complete copy of the books on a data medium. What the tax adviser asks for is a BMD or RZL interchange file, the import formats of the two accounting suites Austrian practices run. The only constraint on where we run is that primary records kept abroad must be brought into Austria on request and be accessible without difficulty.

For us: Austria needs the same immutable journal as Germany, a five-rate VAT table with a date-and-composition test, a per-invoice reverse-charge threshold, ebInterface output alongside Peppol, and the sixth-of-the-year payroll rule if payroll is ever offered. The tax adviser’s interchange formats matter more than the filing.

18.10France

France has the most prescriptive accounting framework in Europe. It is also in the middle of the largest e-invoicing transition. The Plan Comptable Général is a real national chart of accounts, the numbered list of categories every business books to. It has seven classes, plus an eighth for special items. Regulation ANC 2022-06 modernised it, with new balance-sheet and profit-and-loss layouts in force for financial years opened from 1 January 2025. Above the chart sit three tax regimes: micro, simplified and normal. Then comes the liasse fiscale, the packet of standard forms filed with the profit-tax return. It goes through an approved electronic partner, an intermediary contracted with the tax office; direct entry on the tax portal exists only for some regimes. Annual accounts are filed at the companies registry through the single business window. A small company may keep its profit-and-loss account confidential; a micro company may keep the whole accounts confidential.

The FEC, the fichier des écritures comptables, is the French audit file: a plain text export of every accounting entry, and the most concrete requirement in the section. It has eighteen prescribed columns in a fixed order. The file is named for the taxpayer’s SIREN registration number and the closing date. It is demanded at the start of every tax audit for each year under audit, and must be producible on request for any year still open. It is valid only over validated entries: entries that have been locked, numbered in sequence and can no longer be changed. That is why French law effectively requires irreversible entry validation and sequential numbering per journal. Failing to produce a correct FEC costs 5,000 euro or 10 per cent of the reassessed tax, and the books may be rejected outright. Businesses that take cash from consumers additionally fall under the anti-fraud rule of the tax code. A till certified NF525 or by the LNE satisfies it, and so, since February 2026 again, does the publisher’s own attestation. Plain accounting software and business-to-business invoicing are outside that rule.

VAT is 20, 10, 5.5 and 2.1 per cent. It is filed on form CA3 monthly, or quarterly when the annual tax due is under 4,000 euro. The simplified regime files once a year on form CA12 with two instalments in July and December; that regime ends on 1 January 2027 and gives way to quarterly CA3 returns on real figures for businesses up to one million euro of turnover. Filing is online, on the tax portal or by EDI (electronic data interchange) through an approved partner; a ledger that files directly must work through such a partner. Import VAT has been self-assessed on the return since 2022: the importer declares and deducts it on the same return instead of paying it at customs, and the import figures arrive pre-filled. Construction sub-contracting is reverse-charged, meaning the buyer rather than the seller reports the tax. Tax on goods is due on delivery. Tax on services is due when the customer pays, unless the supplier opts to account on invoice (débits), and that option must be printed on the invoice. A ledger therefore records which basis applies for each supplier and customer.

The reform is what everything else in France now turns on. Three different things get called e-invoicing, and the difference matters for the next four countries. Clearance: the invoice goes to a state system first and does not legally exist until that system accepts it. Reporting: the invoice goes to the customer, and its data goes to the tax office alongside. Certification: the tax office approves the software itself before it may be used. France is reporting, routed through private platforms. From 1 September 2026 every VAT-registered business in France must be able to receive a structured invoice, and large and mid-size businesses must issue them and file e-reporting. Small and micro businesses must issue and report from 1 September 2027. In practice, from that date a PDF e-mailed between two French businesses is no longer a valid invoice. The state platform stepped back in October 2024 to being a directory and a data collector. Invoices travel between licensed private platforms, the plateformes agréées, of which about 150 were registered by August 2026, and a ledger must either connect to one or become one. The fines are 15 euro per invoice not issued electronically and 250 euro per missed e-reporting transmission, each capped at 15,000 euro a year, though the tax office has said it will not fine businesses making a serious effort during the start-up phase. Alongside the invoices runs e-reporting, a second and separate feed to the tax office: daily totals of consumer sales by rate, data on business invoices to and from abroad, and payment dates and amounts on services taxed on receipt. Its frequency follows the VAT regime, from every ten days to every two months. Four invoice statuses must be exchanged and forwarded to the tax office: submitted, rejected by a platform, refused by the buyer, and paid. Four new invoice mentions arrive with the reform: the customer’s SIREN number, the delivery address where it differs, the nature of the operation (goods, services or both), and whether the supplier accounts for tax on invoices. Formats are Factur-X (a PDF with the invoice XML embedded), UBL and CII, all carrying the European standard EN 16931.

Payments run on EBICS, the bank file-transfer channel France shares with Germany and Switzerland. Bank statements still arrive as the old CFONB fixed-length files alongside the ISO 20022 statement camt.053, and no retirement date has been set. Payment terms are thirty days by default. The payment terms law caps agreed terms at sixty days from the invoice, or forty-five days end of month. Every invoice must print the late-payment penalty rate, at least three times the legal rate and by default the ECB rate plus ten points, and the fixed forty-euro recovery indemnity. Corporation tax is 25 per cent, with a 15 per cent band on the first 42,500 euro of profit for companies under ten million euro of turnover that are mostly owned by individuals. Payroll is the monthly DSN, a single declaration that feeds every social body and carries the income tax withheld from wages. A product that generates it must pass the state’s validation, so it is a specialist product.

For us: the FEC and the September 2026 receiving obligation are the two hard requirements; the platform integration is the expensive one. Factur-X shares its generator with ZUGFeRD, so Germany and France are one build.

18.11Italy

Italy has had for seven years what the rest of Europe is now building, and it is the clearance model in its purest form: the invoice does not go to the customer at all. It goes as a FatturaPA XML file, the national invoice format, to the Sistema di Interscambio (SdI), the tax agency’s exchange system. The SdI checks it, gives it an identifier, delivers it and returns a receipt. An invoice is legally issued only when the SdI accepts it, and it must be sent within twelve days of the sale. Delivery, rejection (the invoice is resent within five days under the same number), non-delivery to the customer’s tax mailbox, and for public bodies acceptance or refusal, are all messages the ledger must handle. Every business and consumer invoice has been in scope since 1 January 2019. Flat-rate taxpayers, the small sole traders under the forfettario regime, joined fully in 2024. Cross-border purchases and sales have been reported through the same channel since 1 July 2022, using document-type codes rather than a separate return.

The consequences for software are specific. Each invoice carries a document-type code from TD01 to TD29 (TD01 an ordinary invoice, TD04 a credit note), a nature code from N1 to N7 saying why no tax is charged where that is the case, a payment-method code, and either the customer’s seven-character recipient code, which routes the invoice through the SdI, or their certified e-mail address (PEC). Self-billing for reverse charge, where the buyer rather than the seller reports the tax, is done by issuing a further document into the system: TD16 for domestic cases, TD17 to TD19 for foreign suppliers, by the fifteenth of the following month. Stamp duty of two euro is due on any invoice whose amounts not subject to VAT (exempt, excluded or flat-rate) exceed 77.47 euro; the agency computes it from the SdI flow and it is settled quarterly. And the invoices must then be preserved under conservazione a norma, the formal digital-preservation regime: an archive package signed with a qualified signature and time-stamp, a named person responsible for preservation, and a written preservation manual. That is done through the revenue agency’s free service or through a preservation provider working to the AgID rules, but not by simply keeping the files. The archive is kept for ten years.

VAT is 22, 10, 5 and 4 per cent. It is settled monthly by the sixteenth, or quarterly for businesses under 500,000 euro (services) or 800,000 euro (other activities), with a one per cent interest charge for quarterly filers. An advance of 88 per cent is paid by 27 December, a quarterly summary of settlements (LIPE) is filed, and an annual return follows between February and April. Withholding tax of 20 per cent is deducted from professional suppliers’ invoices and paid over by the sixteenth of the following month, then certified to the supplier, which makes the purchase ledger unusually active. Corporate tax (IRES) is 24 per cent, plus a regional tax on production (IRAP) of about 3.9 per cent, varying by region. The statutory books, the journal, the VAT registers, the inventory book and the asset register, must be numbered in sequence and producible on demand. They no longer need printing or stamping if they are up to date on the system, and each year’s books must be complete by 31 January of the second following year. Collections often run on Ri.Ba., bank-collected drafts presented at 30, 60 or 90 days end of month in a fixed-record format over the CBI banking network; they are a national instrument outside the SEPA schemes.

For us: Italy is a whole connector, not a configuration: the SdI channel, the receipt handling, the type and nature codes, and a preservation partner. It is the highest-effort country in the chapter and the one with the most existing SQL-Ledger users in the localisation files.

18.12Spain

Spain is where software regulation lands next. The accounting framework is the Plan General de Contabilidad, the national chart and accounting rules, with its own small-entity variant. The statutory books are legalised electronically at the commercial registry, meaning a hashed copy of each book is lodged there, within four months of the year end. The annual accounts are deposited within a month of approval, and approval is due within six months. What is changing is everything around the invoice.

Verifactu is Spain’s reporting rule for invoicing software. It applies from 1 January 2027 for companies and 1 July 2027 for the self-employed; both dates were put back a year in December 2025. Billing software must then produce, for every invoice, a registration record chained to the previous one by a SHA-256 hash, a fingerprint computed so that any alteration breaks the chain. It must print a QR code linking to a verification page at the tax agency, keep an event log, and either send each record to the agency as it is made, which puts the words “VERI*FACTU” on the invoice, or keep signed records in a non-sending mode for inspection. There is no certification: the vendor files a declaration of responsibility that the software complies. Selling non-compliant software costs the producer 150,000 euro a year per product, and using it costs the business 50,000. Businesses already filing under SII are outside it. SII, the immediate supply of information, is the regime for businesses above 6,010,121.04 euro of turnover, monthly-refund registrants and VAT groups: they send each invoice record to the agency within four days, weekends and national holidays excluded, so their VAT books already sit on its servers. Flat-rate module taxpayers and the Basque and Navarre systems are also outside. Separately, the Crea y Crece law’s business-to-business e-invoicing regime got its regulation in April 2026, Royal Decree 238/2026. Its dates hang on a ministerial order approving the public platform’s technical specifications, not yet published as of September 2026. Businesses above eight million euro of turnover must comply twelve months after that order and everyone else twenty-four months after, so roughly late 2027 and late 2028. It accepts Facturae, the Spanish public-sector format, UBL, CII and EDIFACT, and the recipient must report acceptance or rejection and the date of full payment within the same four days. And the three Basque provinces of Álava, Bizkaia and Gipuzkoa run their own older system, TicketBAI, fully mandatory since 1 January 2026, with its own signed chain, QR code and register of approved software. That region must be either implemented deliberately or excluded in writing.

VAT is 21, 10 and 4 per cent. Retailers who are individuals pay an equivalence surcharge, an extra 5.2, 1.4 or 0.5 points charged by their suppliers in place of filing VAT themselves. The Canaries run a separate tax entirely, IGIC at 7 per cent general, and Ceuta and Melilla another, IPSI. Returns go quarterly, or monthly for large businesses, on form 303 with the annual summary 390. Then come the recapitulative statement, form 349, the list of sales to businesses in other EU countries, and form 347, the annual list of counterparties with whom more than 3,005.06 euro was traded, filed by those outside SII. Withholding on professional invoices at 15 per cent, or 7 in the first three years of activity, and on rent of premises at 19 makes purchase-side withholding a core feature rather than an edge case. Corporate tax is 25 per cent with reduced rates for small companies: in 2026, 19 per cent on the first 50,000 euro and 21 above for companies under one million euro of turnover, 23 per cent between one and ten million, and 15 per cent for new companies in their first two profitable years. Bank statements arrive as Norma 43, a fixed-width national statement format still more common than the ISO 20022 camt.053, with no retirement date. Payment files go out as the Spanish adaptations of pain.001 for transfers and pain.008 for direct debits.

For us: Spain means a hash chain, a QR code and an event log inside the invoicing path by 2027, plus Norma 43 import. The hash chain is the same idea Portugal already requires and the one our RMA document archive already implements for a different purpose.

18.13Portugal

Portugal regulates invoicing software more tightly than any other country in this survey, and it does so in a way that decides at the outset whether a foreign product may be sold there at all. This is the certification model. Decree-Law 28/2019 requires certified invoicing software of any taxpayer established in Portugal who meets any one of three tests: turnover above 50,000 euro in the previous year; organised accounting, meaning full double-entry books, whether required or chosen; or the use of invoicing software at all. That third limb is the one foreign vendors misread. The 50,000 euro figure is only the first test, and there is no small-business exemption for software. A business below the threshold may write invoices by hand or use the tax authority’s own free application, but the moment it uses a program, the program must be certified. Accounting-only software needs no certificate, but it owes the same integrity, audit-trail, documentation and export duties.

What certification requires. The producer applies to the tax authority on form Modelo 24, supplies an RSA public key, the public half of a signing key pair, and receives a certificate number within about thirty days, after conformity tests. That number must be printed on every document as “Processado por programa certificado n.º nnnn/AT”, preceded by four characters of the document’s signature. Every invoice, credit note and goods-movement document is then chained. The program builds a message from the document date, the date and time of entry into the system, the document number and the gross total, joined by semicolons and followed by the signature of the previous document of the same type and series. It signs that message with the private key and prints characters 1, 11, 21 and 31 of the result on the document. The key length and hash are prescribed: RSA at 1024 bits and SHA-1, giving a 172-character signature. Receipts are not signed and print “Emitido por programa certificado n.º nnnn/AT” instead. A cloud vendor can be certified; German, Spanish, Italian, Dutch and French producers are on the published list. But the private key is the producer’s, it signs every tenant’s documents, and the rules require it to be protected during signing. That shapes the architecture rather than merely the paperwork. Changing the key means a new application, and a key version number is stored with every signed record.

ATCUD and the QR code sit on top of that. ATCUD is the unique document code. Each document series must be registered with the tax authority before use, which returns a validation code of at least eight characters. The document then carries an ATCUD made of that code, a hyphen and the sequential number, on every page; that has been mandatory since 1 January 2023. Since 1 January 2022 every invoice also carries a QR code of at least 30 by 30 millimetres with a prescribed field list: both tax numbers, the customer’s country, the document type and status, the date, the unique identifier, the ATCUD, the tax breakdown by rate and region, the totals, the four signature characters and the certificate number, with an optional field for payment details. A Portuguese invoice is, in effect, a signed and registered object.

SAF-T (PT) is the reporting channel: the Standard Audit File for Tax, an XML export of master data and documents in the Portuguese layout, version 1.04_01. The invoicing variant is communicated monthly, by the fifth of the following month, through the e-Fatura portal or a web service, and a nil return is required for a month with no invoices. The accounting variant, long deferred, is now due first for financial year 2027, filed in 2028, and will pre-fill the annual business return; every general-ledger account must carry a taxonomy code for it. Inventories are reported each January. Retention is ten years, and covers the system documentation as well as the data.

VAT is 23, 13 and 6 per cent on the mainland, with the Azores at 16, 9 and 4 and Madeira at 22, 12 and 4: three rate sets in one country, chosen by the place of supply, so the rate table is keyed on region as well as date. The exemption for small operations sits at 15,000 euro of national turnover under article 53, rewritten in 2025 to carry the European small-business scheme. Returns are monthly at or above 650,000 euro of turnover and quarterly below, due on the twentieth of the second month following, with payment by the twenty-fifth; the June and second-quarter returns are extended to September. Cash accounting, where VAT falls due when the customer pays rather than when the invoice is issued, is available up to 500,000 euro of turnover. Corporate tax is on a legislated path down: 20 per cent for 2025, 19 for 2026, 18 for 2027 and 17 from 2028, with a reduced rate on the first 50,000 euro for small and medium companies of 16 per cent in 2025 and 15 from 2026, plus a municipal surcharge of up to 1.5 per cent and a state surcharge of 3, 5 or 9 per cent on profits above 1.5, 7.5 and 35 million euro. Above all sits tributação autónoma, autonomous taxation: a separate tax on certain expenses, payable even in a loss year, with nothing deductible against it. It falls on cars by purchase price (8, 25 or 32 per cent below 37,500 euro, up to 45,000, and above), on representation expenses at 10 per cent, on per diems and mileage at 5, on undocumented expenses at 50, and on several other categories. The rates rise by ten points when the company reports a tax loss, though for 2026 that rise is suspended for companies with a profit in one of the three prior years and clean filings. It is a real computation a ledger must carry rather than a disclosure.

Payments run on the Multibanco network, the national ATM and payment system. The reference a Portuguese invoice carries is a five-digit entity number and a nine-digit reference, obtained through a payment provider or the bank, and that reference is how the receipt is matched to the invoice; it can ride inside the QR code’s payment field. Plain PDF invoices count as electronic invoices until 31 December 2026. From 1 January 2027 a PDF needs a qualified electronic signature or seal, the EU-recognised digital signature, to count. That requirement has been put off by every budget since 2020 and is currently set to bite on that date.

One rule bears directly on where we run. Hosting the invoicing system or the archive inside the European Union needs no permission. Hosting either outside it requires individual prior authorisation from the tax authority for each customer, with online access available to inspectors from terminals in Portugal. The customer must also tell the tax authority where its electronic archive is kept, so the vendor must publish the hosting country. Our European region satisfies this; a decision to serve Portugal from anywhere else would not.

For us: Portugal is a deliberate project, not a translation. The certification, the key handling, the chain, the ATCUD series registration and the monthly SAF-T are together the largest single-country build in this chapter, and none of it can be partially done. An uncertified program is unlawful to use, not merely non-compliant: it is the business using it that is fined, and a revoked certificate puts every customer of that product out of compliance at once.

18.14The Netherlands, Belgium and Luxembourg

The three are usually sold together, and they are not alike. The Netherlands is the most standardised country in Europe for filing by machine. Annual accounts, VAT returns, the recapitulative statement (the periodic list of sales to VAT-registered customers in other EU countries) and the corporate tax return all travel as XBRL. XBRL is a machine-readable format in which every figure carries a tag saying what it is. They go through one government gateway, Digipoort. The sender proves its identity with a government-issued PKIoverheid certificate, or uses a filing service that holds one. Micro and small companies have filed their accounts this way since financial year 2016; since financial year 2025 even large companies do. The reference chart of accounts, the Referentie Grootboekschema or RGS, is a standard list of account codes. (A chart of accounts is the numbered list of categories a business books to.) The RGS is voluntary, but the accountant’s tools expect it, so every general-ledger account should carry its RGS code. The audit file is the XAF, an XML export of the whole ledger that the tax office demands at every audit. Version 3.2 is the accepted standard; a version 4.0 exists for newer software. VAT is 21 and 9 per cent, filed quarterly by default. A small-business exemption lets a business with turnover of 20,000 euro or less a year stay out of VAT altogether. Nearly every importer holds an import deferment licence, the article 23 licence: import VAT is declared on the return instead of being paid at the border. Construction uses the reverse charge along the subcontracting chain, where the buyer rather than the seller reports the tax. iDEAL, the bank-transfer method behind most Dutch online shopping, is being folded into the pan-European Wero scheme: joint branding since 29 January 2026, transactions moving from April 2026, every Dutch bank connected by October 2026, and the migration due to finish by 31 December 2027. Since 1 July 2022 a large company must pay a small supplier within thirty days.

Belgium is, as of 1 January 2026, the most demanding country on this list for a small business. Every VAT-registered business established in Belgium must issue and receive structured invoices for domestic business-to-business sales. A structured invoice is a data file a computer can read, not a PDF. They travel over Peppol, the open European network in which accredited access points hand invoices to each other, much as e-mail providers hand mail to each other. There is no state platform and no PDF fallback: the government’s Hermes service, which used to turn Peppol invoices into PDF e-mails for unregistered receivers, was switched off on 31 December 2025. In practice, a PDF e-mailed between two obliged businesses is no longer a valid invoice, and the customer may refuse to deduct the VAT on it. Outside the mandate are sales to consumers, businesses under the 25,000-euro small-enterprise scheme, suppliers whose activities are VAT-exempt (doctors, schools and the like), flat-rate farmers, bankrupt taxpayers, and foreign businesses that hold a Belgian VAT number but have no establishment in Belgium. The tax office imposed no sanctions until 31 March 2026 on businesses that could show they were preparing. Since 1 April 2026 the fines are 1,500 euro for a first breach, 3,000 for a second and 5,000 for each one after that. The next step is near-real-time reporting of the same invoice data to the tax office from 1 January 2028, at which point the annual customer listing disappears. The cabinet approved that draft on 18 July 2026, but it is not yet law. Everything else about Belgium is conventional except two national fixtures. The first is the structured communication, a twelve-digit payment reference printed between plus signs, +++123/4567/89012+++. Its last two digits are the remainder when the first ten are divided by 97, with a remainder of nought written as 97. The second is CODA, the coded daily bank statement: every Belgian bank delivers each day’s transactions as a fixed-format file that carries the structured communication, so the ledger can match payments to invoices automatically. Every Belgian package imports it, and it arrives through Isabel, Ponto or CodaBox. The VAT chain reform replaced the old VAT current account with a provision account from 1 May 2026; credits sit there and can pay any VAT debt or be refunded on request. Disallowed expenses are a real computation the ledger must carry. These are costs the tax office refuses to accept as deductions from profit: restaurant costs are only 69 per cent deductible, receptions and business gifts 50 per cent. Cars follow a carbon-dioxide formula, and fossil-fuel cars ordered from 1 July 2023 taper from 50 per cent in 2026 to 25 in 2027 and nothing from 2028.

Luxembourg is small and tidy. The chart of accounts is standardised, the Plan Comptable Normalisé, and it is itself filed: the balance sheet, the profit and loss account and the trial balance by standard account go through the eCDF platform before the accounts are deposited at the business register. The audit file is called FAIA. It is Luxembourg’s version of SAF-T, the OECD’s standard audit file for tax, a fixed XML layout in which the whole ledger is handed to an inspector; the VAT authority asks for it in an audit. VAT is 17 per cent, the lowest standard rate in the Union, with 14, 8 and 3 per cent below it. Peppol has been compulsory for invoices to public bodies since 18 March 2023. A business-to-business mandate was approved by the government on 17 July 2026 as a draft law, Bill 8815. Under it every company must be able to receive structured invoices from 1 January 2028, large and medium companies must issue them from 1 July 2028, and all remaining companies from 1 January 2029. It is not yet enacted.

18.15The United Kingdom and Ireland

The two share accounting standards but not a tax system: the United Kingdom left the European VAT system, and Ireland remains inside it with its own way of administering tax. Both now put more weight on the software than on the paperwork.

Making Tax Digital is the United Kingdom’s distinguishing feature. It is the tax authority’s rule that records must be kept in software and returns sent from that software by API, a direct machine-to-machine connection, with no paper form. It is the single largest requirement in this chapter for a small-business ledger. VAT has been filed this way since 2019. The rule includes a duty of digital links between the records and the return: no figure may be re-keyed by hand anywhere in the chain. From 6 April 2026 the same applies to income tax for sole traders and landlords with more than 50,000 pounds of qualifying income. The threshold drops to 30,000 pounds from 6 April 2027 and to 20,000 from 6 April 2028. Such a taxpayer sends four cumulative quarterly updates, due by 7 August, 7 November, 7 February and 7 May, then a final declaration by 31 January. All of it goes through the tax authority’s interface from recognised software. There is no paper alternative for those taxpayers. A ledger that wants British sole traders must be on the tax authority’s recognised list, hold API credentials, and send the fraud-prevention headers the interface demands: details of the device and user that every request must carry.

VAT is 20, 5 and zero per cent, and a business must register once taxable turnover passes 90,000 pounds in twelve months. The zero rate is a genuine rate, not an exemption. It covers most food, books and children’s clothing, which makes the rate table longer than it looks. The flat-rate scheme (a fixed percentage of sales instead of invoice-by-invoice VAT) and cash accounting (VAT on money received rather than on invoices issued) are widely used. Construction has a domestic reverse charge, where the customer rather than the builder accounts for the VAT. Separately, the Construction Industry Scheme makes a contractor verify each subcontractor with the tax authority and deduct 20 per cent (registered) or 30 per cent (unregistered) from the labour part of every payment; some subcontractors are approved for gross payment at nought. The contractor files a monthly return by the 19th. Payroll is real-time: a submission to the tax authority on or before every payday. Accounts go to Companies House, the company register. The tax return goes to the revenue with accounts in inline XBRL, a web page whose figures carry hidden machine-readable tags. The plan to force software-only filing at Companies House from April 2027 was paused on 28 January 2026. It remains under review, and at least 21 months’ notice has been promised before any new date. E-invoicing was announced at the November 2025 budget for April 2029, covering all VAT invoices between businesses and to public bodies, with no real-time reporting to the tax office at first. Peppol was confirmed as the network on 23 June 2026, and a roadmap with milestones is due at the autumn 2026 budget. Payments are not SEPA except in euro. Sterling moves by Faster Payments within seconds, or by Bacs on a three-day cycle, addressed by sort code and account number. Bank feeds come through Open Banking via the usual aggregators.

Ireland shares the accounting standards and diverges on tax administration. Everything goes through the Revenue Online Service, including two mechanisms a ledger must implement rather than merely report. The first is Relevant Contracts Tax, a withholding tax in construction, forestry and meat processing. The principal contractor notifies Revenue of each contract, then notifies each payment before making it, and receives back a deduction authorisation telling it to withhold nought, twenty or thirty-five per cent before paying the subcontractor. The second is professional services withholding tax: public bodies deduct twenty per cent from professional fees, and the payee claims it back as a credit. Payroll has been real-time since 2019, with a submission for every payslip on or before payday. Since 2024 the enhanced reporting requirements add travel and subsistence payments, the small benefit exemption (tax-free non-cash gifts, up to five a year totalling 1,500 euro) and the remote-working allowance of 3.20 euro a day to that real-time feed. Auto-enrolment pensions, the My Future Fund, started on 1 January 2026 at 1.5 per cent each from employer and employee. VAT is 23, 13.5 and 9 per cent, with food, catering and hairdressing moving from 13.5 to 9 on 1 July 2026. Returns are filed every two months, with an annual return of trading details. A business may account for VAT on cash received rather than on invoices issued up to two million euro of turnover. E-invoicing and real-time reporting arrive for large corporates in November 2028, for every business trading with other EU countries in November 2029, and for everyone under the European rule on 1 July 2030; all businesses must be able to receive e-invoices from November 2028. Corporation tax is famously 12.5 per cent on trading income and 25 on the rest. A close-company surcharge, an extra charge on investment income that a small owner-managed company keeps rather than pays out, catches small companies by surprise.

18.16The Nordics

Four countries, three currencies, one shared habit: the state publishes a technical standard and every product implements it. Interoperability is therefore high, and the entry cost is a fixed list of files.

Sweden. The gate is SIE, the standard file in which Swedish bookkeeping moves between programs. It is plain text in an old code page (IBM PC-8, code page 437). It holds the chart, opening and closing balances, every voucher with its transactions, the tax-form code of each account, and cost centres and projects. Types 1 to 4 differ in how much they carry: type 4E is the full export, 4I the import of vouchers, and SIE 5 is a newer XML version that remains optional. Every Swedish accounting program reads and writes it. An accountant tests a new product by exporting a year and importing it elsewhere; failing that test ends the evaluation. The chart is BAS, republished every year, and every account carries the SRU field code that maps it to a line of the tax return. VAT is 25, 12 and 6 per cent. Food moves from 12 to 6 per cent on 1 April 2026 until 31 December 2027, and is due back at 12 from 1 January 2028 unless extended; restaurant meals stay at 12. The return is a form of numbered boxes, filed on screen or as an XML upload, monthly, quarterly or annually by turnover. Invoices carry an OCR reference, a digits-only payment reference with a Luhn check digit and, optionally, a length digit, tied to the seller’s bankgiro number. The Bankgirot file infrastructure is being retired in favour of ISO 20022 bank files: the old Bankgiro payment formats stop being accepted on 1 September 2026, though bankgiro numbers and the OCR reference survive. Annual accounts go to the companies registry, Bolagsverket, on paper or digitally in inline XBRL; the digital route is expected but not yet compulsory. Late-payment interest is the reference rate plus eight points, 10 per cent for all of 2026, with a fixed fee of 450 kronor per late invoice.

Denmark. The Bookkeeping Act of 2022 is the most direct regulation of accounting software in Europe. A digital bookkeeping system must be registered with the business authority, Erhvervsstyrelsen, and must by law offer four things: sending and receiving e-invoices (OIOUBL over NemHandel, and Peppol BIS), bank reconciliation with the bank account in the chart and unmatched items shown, a mapping of every account and VAT code to the public standard chart and standard VAT codes, and a Danish SAF-T export. The provider must also keep backups, with at least one copy held inside the European Economic Area. A business may use an unregistered system, such as a foreign product, only by guaranteeing the same requirements itself. The phases ran from financial years starting 1 July 2024 for companies that file annual reports and use a registered system, 1 January 2025 for the same companies on unregistered systems, and 1 January 2026 for every other business whose turnover exceeded 300,000 kroner in two consecutive years. The SAF-T export is built on that public standard chart and those standard VAT codes, so every account and tax code in a Danish tenant needs a mapping. Version 1.0 dates from November 2022; version 2.0 was finalised in February 2026, and registered systems must support it from 1 January 2027. E-invoicing runs on NemHandel, the national network, in the OIOUBL format and over Peppol. The planned OIOUBL 3.0 was cancelled in March 2026; OIOUBL 2.1 stays until NemHandel moves to a Peppol BIS 4 profile from 2028. VAT is a single 25 per cent rate. That makes the tax engine the simplest in Europe and the reporting duties the heaviest.

Norway. Not in the Union, and the most API-forward country here. Since 2022 the VAT return has not been a form with boxes but a list of amounts per standard SAF-T tax code, sent straight from the accounting system through the tax authority’s interface. SAF-T Financial itself, the full ledger export, must be produced on demand; version 1.30 is valid now, and version 1.40 becomes the only valid schema on 1 January 2027. Every invoice carries a KID number, a customer payment reference of up to 25 digits with a modulo-10 or modulo-11 check digit. The payer’s bank validates it and passes it to the seller, so incoming payments are matched from it automatically. Invoice numbers must be assigned by the system in an unbroken sequence, an issued invoice may never be edited, and a correction is always a credit note. E-invoicing in the EHF format, the Norwegian profile of Peppol, becomes compulsory to issue on 1 January 2027 and to receive on 1 January 2030, when electronic bookkeeping also becomes compulsory. Annual accounts go to the register at Brønnøysund through the Altinn portal as a structured form plus PDF, not XBRL. Payroll is the monthly a-melding, one submission by the 5th that serves the tax office, the labour and welfare authority and the statistics office.

Finland. Two things stand out. Every wage payment is reported to the national Incomes Register, per employee, within five calendar days of the payment date, by interface. A short employer’s summary of contributions follows by the 5th of the next month, and there is no annual wage return at all. And every invoice carries a viitenumero, the Finnish reference number: 4 to 20 digits whose last digit is a check computed with the weights 7, 3 and 1. In print it is joined by a 54-digit bank barcode encoding account, amount, reference and due date, which a payer scans. E-invoicing has no mandate, but a law of 2019 gives any business with turnover above 10,000 euro the right to demand a structured invoice from its suppliers, which achieved the same result. The formats are Finvoice and Peppol, exchanged through operators. VAT is 25.5 per cent since 1 September 2024, with 13.5 per cent (down from 14 on 1 January 2026) and 10 per cent below it. Returns are monthly by the twelfth of the second following month, through the tax authority’s API. Bookkeeping law demands an unbroken audit chain from voucher to statement, and vouchers are kept six years and books ten.

18.17Central Europe

These are the countries where the tax office asks for the most data, most often, in the most structured form. None of them can be served by a generic product.

Poland combines two systems. KSeF is the national e-invoice system: every domestic business invoice is sent to the state as XML, checked, given a KSeF number and stored, and the buyer collects it from there. Issuing through it became compulsory on 1 February 2026 for taxpayers whose 2024 sales exceeded 200 million zloty, on 1 April 2026 for everyone else, and from 1 January 2027 for the smallest, those invoicing 10,000 zloty a month or less. Receiving through KSeF has been compulsory for all since 1 February 2026. The format is the national FA(3) schema. Any printed copy carries QR codes, and an offline mode lets an invoice be handed over first and uploaded by the next business day. Alongside it, JPK is a family of extraction files, the Polish form of the audit file. The monthly VAT file carries the return plus every sale and purchase, with transaction-group markers and document-type codes. An annual accounting-books file, with a tag on every account and a counterparty number on every entry, became compulsory for the largest taxpayers for 2025; it extends to all corporate taxpayers filing monthly VAT for financial years from 1 January 2026, and to everyone else from 2027. There is a fixed-asset file, and more on demand. Two further mechanisms are unique. The white list is the tax office’s register of taxpayers’ bank accounts. Before any payment of 15,000 zloty or more to another business, the payee’s account must be checked against it, or the expense is disallowed for tax; the check reference is kept as evidence. Split payment sends the VAT portion of certain transfers to a restricted VAT account of the supplier. It is compulsory for listed goods such as steel, fuel and construction services on invoices of 15,000 zloty or more, and it is carried as a structured message inside the payment file.

Czechia requires the kontrolní hlášení, the control statement: a list of individual invoices that the tax office cross-matches against what the other party filed. Companies file it every month; sole traders file it with their VAT return. It lists every domestic invoice above 10,000 koruna including VAT, issued or received, with the counterparty’s tax number and the supplier’s own document number. The purchase ledger must therefore capture the supplier’s invoice number exactly, or the match fails. VAT is 21 and 12 per cent. Payments carry a variable symbol, a numeric field of up to ten digits that by convention holds the invoice number, and a QR payment code defined by the banking association. Statements still arrive in the old GPC format alongside camt.053. There is no e-invoicing mandate. A new accounting act is before parliament with a planned start of 1 January 2028, possibly 2029; it should be watched but not yet built for.

Hungary has had real-time invoice reporting since 1 July 2018. Every invoice, correction and cancellation is sent to the tax office as XML the moment the invoicing program closes it, without anyone pressing a button. The connection signs each request and decrypts a token, and the taxpayer must register which invoicing program it uses. A separate decree requires every invoicing program to offer an audit export of invoice data by date range or number range in a prescribed XML. VAT is 27 per cent, the highest in the Union, with 18 and 5 below. The VAT return carries an annexe listing every domestic supplier invoice on which tax was deducted. The tax office’s pre-filled return, built from the real-time data, has existed since 2024 and becomes the only way to file from 1 January 2027. Numbers must be gap-free, and an invoice may never be edited after issue, only modified or cancelled by a further document.

Slovakia mandates Peppol-based invoicing from 1 January 2027, with the delivery provider reporting each invoice to the tax office at the moment of issue. It files a control statement like the Czech one, monthly by the 25th. And since 1 April 2025 it has levied a financial transaction tax: 0.4 per cent of every outgoing payment, capped at 40 euro, withheld by the bank and shown on the statement. The books must post it from the statement, a genuinely new kind of line item. Sole traders have been exempt since 1 January 2026; companies still pay.

18.18The Baltics

Estonia and Latvia share a corporate tax model that changes what a ledger computes. It is a distribution tax: there is no tax on profit a company keeps, and tax falls only when value leaves the company. The rate is twenty-two over seventy-eight in Estonia and twenty over eighty in Latvia, meaning 22 or 20 per cent of the gross sum out of which the tax is paid. It also falls on deemed distributions such as entertainment, gifts and non-business expenses. The year-end module is therefore not a tax computation on profit but a classification of outgoing value.

Both file VAT with invoice-level annexes. Estonia’s lists every sales and purchase invoice for any counterparty whose total in the month reaches 1,000 euro; Latvia’s lists every document of 150 euro or more. The return is therefore generated from the ledger rather than from balances. Estonia reports payroll, dividends and fringe benefits on one monthly declaration, the TSD, by the 10th. It uses a reference number on invoices with the same 7-3-1 check digit as Finland. And since 1 July 2025 a seller must send a structured invoice whenever the buyer has registered itself as an e-invoice recipient in the business register. Latvia made invoicing to public bodies compulsory in January 2025 and has legislated for business-to-business from 1 January 2028; until then PDF invoices remain valid. Both administrations expose machine interfaces and expect software to use them.

18.19The audit file, country by country

An audit file is a copy of the books in a form a computer can read, handed to the tax office when it asks. Every tax office in Europe can ask for one. About half of them have written down exactly what the file must look like. This is the least glamorous table in the chapter. It is also the one that decides whether an accountant will recommend a product, because the accountant is the person who has to produce the file.

18.20Where our ledger stands

This table measures our ledger against the whole survey rather than against any one country. Each row carries one of four coloured marks, which are the book’s own. have means the feature works today. partial means the substance exists somewhere in our code, but not as a finished feature in the ledger itself. build means the feature is absent and a business in Europe needs it. skip means the feature is absent and not worth building.

18.21What to build, in order

1Structured addresses, everywhere

Split every customer, vendor and company address into street, building number, postcode, town and a two-letter ISO country code. Ship a migration that parses the existing free-text addresses, and a screen for fixing the ones it cannot parse. Nothing else in this chapter has a fixed date as close as 15 November 2026. On that date the SEPA payment rulebooks stop accepting unstructured addresses in payment files, and the Swiss payment standards change over in the same month. In practice, from then on a payment file with a one-line address is rejected by the bank. Structured addresses are also the precondition for QR-bills, for EN 16931 e-invoices and for verification of payee, the check a bank now makes that the payee name matches the account.

Touches: SL/CT.pm, bin/mozilla/ct.pl, the address templates, one schema upgrade. Effort: small, plus the data migration.

2An immutable journal and a real audit trail

Posted rows become append-only, meaning they can be added to but never altered or deleted. Corrections are made by reversing entries. The change log records who changed what, when, and the values before and after. Accounting periods can be locked. Document numbers are assigned by the system, per series and per year, and cannot be overtyped. This is one piece of work that satisfies German GoBD, Swiss GeBüV, the French rule that records must be unalterable, and the Polish, Norwegian, Danish, Finnish and Hungarian equivalents at once. Without it the product cannot honestly be sold anywhere in Europe. Generate the system documentation as a PDF while in there, because several of those regimes require a written description of the system.

Touches: SL/Form.pm audittrail, every posting path, SL/AM.pm defaults. Effort: medium.

3The EN 16931 invoice document

Build one canonical invoice model. Write it out as UBL 2.1 and as CII, the two XML syntaxes the European standard allows. Validate it against the European and Peppol rule sets. Render it as ZUGFeRD or Factur-X by embedding the XML inside the PDF our templates already produce. That single artefact satisfies Germany from 2025, France from 2026, and the public sector of every country in the survey. It is also the input to everything in item 4. Add now the three fields the 2030 rules will want: the seller’s bank account, the due dates, and the number of the invoice being corrected.

Touches: a new SL/EInvoice.pm, SL/IS.pm, the LaTeX and HTML template path. Effort: medium.

4A Peppol access point, integrated not built

Peppol is the network over which e-invoices travel, and an access point is the gateway a business uses to join it. Contract with one access-point provider rather than becoming one. Register each tenant on the network under the right national identifier scheme. Send invoices, receive them into a draft purchase invoice, and handle the message-level responses that say whether an invoice was accepted. This covers Belgium today, Norway and Slovakia in 2027, Ireland in 2028, Britain in 2029, the Netherlands in 2030 if its plan becomes law, and every public body now.

Touches: the appserver, SL/EInvoice.pm, the panel for registration. Effort: medium, mostly integration.

5The bank-file pair, moved into the ledger

Lift the pain.001.001.09 payment-file export and the camt.053, camt.054 and CSV statement import out of the RMA cockpit and into the ledger. Put the reference generator behind it. A payment reference is the number printed on an invoice that lets the bank statement be matched back to it, and each country has its own: the Swiss QR reference, the international RF reference, the Swedish OCR, the Norwegian KID, the Finnish viitenumero, the Belgian structured communication and the Czech variable symbol. They are one function with a country parameter and a check-digit rule each. Then build the codes that print them: the Swiss QR-bill first, the EPC QR code second.

Touches: SL/BK.pm new, rma/rma.pl as the source, the invoice templates. Effort: medium.

6The tax-treatment engine

Replace the single tax code per customer with a derivation from the facts of the sale: the type of supply (goods or services), the country the goods ship from and the country they ship to, the customer’s status (a business or a consumer, VAT-registered or not) and our own VAT registrations. The result is a treatment code that carries both the wording the invoice must show and the box on the VAT return the amount goes in. Add validation of customers’ VAT numbers with the results stored, the recapitulative statement (the list of sales to businesses in other EU countries that the tax office requires) and the One-Stop-Shop rate tables (the scheme that lets one VAT return cover sales to consumers across the EU). This is what makes any country’s VAT return possible rather than a special case.

Touches: SL/AA.pm, SL/IS.pm, SL/IR.pm, SL/AM.pm, one schema upgrade. Effort: large.

7Country returns, three at a time

On top of item 6, each VAT return is a mapping of treatment codes to boxes plus a file format. Take them in the order of the customers we have. Switzerland is done in RMA and needs only the eCH-0217 upload, the XML file the Swiss tax office accepts. Then Germany through ELSTER, Austria through FinanzOnline and the Netherlands through Digipoort, the three national tax portals. Each is days, not weeks, once the engine exists.

Effort: small each.

8The audit files

One export framework, five formats: SIE for Sweden, FEC for France, XAF for the Netherlands, SAF-T for Norway, Portugal and Denmark, and the DATEV posting batch for Germany. They are all the same query over the journal, the accounts, the customers and vendors and the tax codes. Only the file layout and the code mappings differ. Each one is the difference between an accountant trying the product and dismissing it.

Touches: a new SL/Export/ tree. Effort: medium in aggregate.

9The dunning tables

Dunning is the sending of reminders for unpaid invoices. The tables hold the statutory payment terms of thirty and sixty days, the late-payment interest rate per country, which is reset every half year, the fixed compensation for late payment in its local amount, and the wording each country requires on the invoice. A table and a template, and it closes a gap in every section above.

Touches: SL/AA.pm, the reminder screens. Effort: small.

10Then, and only then, a hard country

Italy, Poland and Hungary each need a full connector to a state platform through which invoices must pass. Portugal and Spain need the product itself certified or its records chained. Do none of them until the first nine are done. Then do the one where a customer is waiting. Belgium, by contrast, needs only items 3 and 4. That is why it is the best first country to serve among those with a mandate.

18.22What we will not build

National payroll. Every country in this chapter has a payroll reporting standard, a table of social contributions that changes every year and, in several cases, a certification regime. Switzerland alone costs 4,500 francs a year in certification fees and needs a specialist. The payroll module stays what it is, user-defined wages and deductions. The answer to a prospect is a named partner per country, exactly as Infinity does in chapter 17. Cash registers and point-of-sale fiscalisation, the state-controlled sealing of till receipts, are ruled out for the same reason in eight countries. Becoming a licensed invoicing platform in France or an access point in Peppol are both businesses, not features. And the tax computation itself, meaning depreciation tables, disallowed expenses and advance payments, is worth flagging in the chart of accounts and worth exporting. The tax return, though, is the accountant’s work and should stay there.

18.23Glossary

18.24Sources