International E-Invoicing: Legal Requirements by Country

Why Looking Beyond Germany Matters

Across much of Europe, electronic invoicing is no longer a future topic, but an established or imminent legal requirement. While countries like Italy and Romania have relied on centralised clearance models for years, others – such as Germany and Spain – are just beginning phased rollouts. Behind most European initiatives lies the EU reform ViDA (VAT in the Digital Age), aiming for a harmonised digital reporting system across the EU in the long run. Until then, regulation remains national and fragmented – with tangible consequences for cross-border businesses. We have previously analysed the German e-invoicing mandate and ViDA fundamentals; here is our country-by-country overview for the largest economies in and outside the EU.

Overview of Mandates

The following table summarises formats, mandates, legal foundations, and thresholds per country. Detailed country sections follow below.

| Country | Format / Standard | B2G Mandate | B2B Mandate | B2C Mandate | Legal Basis | Threshold | | --- | --- | --- | --- | --- | --- | --- | | Germany | XRechnung, ZUGFeRD (EN 16931 compliant) | Yes, since 27/11/2020 | Phased: Reception from 01/01/2025 (all); Issuance from 01/01/2027 (>€800,000 turnover); from 01/01/2028 (all) | No (not planned) | Growth Opportunities Act (2024), EN 16931 / EU ViDA | €800,000 annual turnover (transitional period until 2027) | | Italy | FatturaPA (XML) | Yes, since 2014/2015 | Yes, since 01/01/2019 | Yes, since 01/01/2019 | National law; centralised clearance system Sistema di Interscambio (SdI) | None – applies to all businesses | | Poland | FA(3) / KSeF (national XML schema) | – | Phased: from 01/02/2026 (>PLN 200m ≈ €46m); from 01/04/2026 (all others) | Planned, tied to B2B | KSeF Act (national VAT law) | PLN 200m (~€46m) for phase 1 | | France | Factur-X (Hybrid PDF+XML), UBL, CII | Yes, since 01/01/2020 | Phased: Reception from 01/09/2026 (all); Issuance from 01/09/2026 (large/mid-caps); from 01/09/2027 (SMEs/micro-enterprises) | Via e-reporting mandate (linked to B2B) | Ordonnance n° 2021-1190 / Loi de Finances; EU ViDA compliant | Tiered by company size | | Austria | ebInterface, Peppol BIS 3.0, CIUS-AT-NAT/GOV | Yes, since 01/01/2014 | No – voluntary, no mandate announced | No | Federal E-Invoicing Act (ERG) | – | | Belgium | Peppol BIS (mandatory via Peppol network) | Yes, phased 11/2022–11/2023 (by contract value) | Yes, since 01/01/2026 (Issuance & Reception) | No | Law of 06/02/2024 on mandatory e-invoicing | None – all VAT-registered businesses | | Romania | RO e-Factura (national XML) | Yes | Yes, since July 2022 (high-risk goods) / January 2024 (general); SME grace period (penalty-free) until 01/07/2026 | Yes, since 01/01/2025 | GEO No. 89/2025 and amending ordinances; centralised clearance system (ANAF) | €500,000 turnover (SME grace period) | | Denmark | OIOUBL (migration to Peppol BIS 4 planned by 2029) | Yes, since 2005 | No – no general B2B mandate; automatic NemHandel registration as default from 2026 under digital bookkeeping mandate | No | Bogføringslov (Bookkeeping Act) | – | | Spain | FacturaE, UBL, CII, EDIFACT (EN 16931) | Yes, since 2015 | Phased: from 01/10/2027 (>€8m turnover); from 01/10/2028 (all others) – regulation adopted 24/03/2026 | Indirectly covered via status reporting | Ley 18/2022 "Crea y Crece" Art. 12; Real Decreto of 24/03/2026 | €8m annual turnover for phase 1 | | Switzerland | UBL 2.1 / UN/CEFACT CII (eCH-0069 / swissDIGIN), eBill | Yes, since 01/01/2016 (Federal Administration) | No – no B2B mandate at federal level, voluntary/decentralised; cantons/municipalities may differ | No | Federal procurement law / internal directives | From CHF 5,000 per invoice (B2G) | | Turkey | e-Fatura (UBL-TR) / e-Arşiv | Yes | Yes, phased: Registration mandate e-Fatura from 01/07/2026 for businesses with 2025 turnover ≥ TRY 3m (special threshold TRY 500,000 for e-commerce, real estate, automotive, hospitality); from 01/01/2026 e-Arşiv mandatory for all non-registered taxpayers | Covered via e-Arşiv | General Communiqué No. 509 on Tax Procedure Law (Vergi Usul Kanunu) | TRY 3m (~€55,600); TRY 500,000 (~€9,300) sector-specific | | United Kingdom (UK) | Peppol BIS 3.0 | Yes (NHS suppliers) | Announced from April 2029 (subject to confirmation in Budget 2026); currently voluntary | Not planned | Consultation "Promoting electronic invoicing across UK businesses and the public sector" (HMRC/DBT) | TBD | | Netherlands | Peppol BIS, EN 16931 | Yes (since ~2017, via Peppol) | No mandate yet – cross-border from 01/07/2030 (EU ViDA); domestic reporting potentially from 2032; draft bill for consultation expected Q4 2026, legislation by mid-2028 | No | EU ViDA Directive; Ministry of Finance evaluation (10/03/2026) | – | | Sweden | Peppol BIS Billing 3 (Svefaktura/EDIFACT increasingly restricted) | Yes, since 01/04/2019 | No mandate yet – official inquiry running since 05/02/2026, legislative proposal expected by 30/11/2027, aligned with EU ViDA deadline 01/07/2030 | No | Ministry of Finance directive (Feb 2026) on ViDA implementation | TBD | | Portugal | CIUS-PT (EN 16931 / UBL 2.1) | Yes (EU Directive 2014/55/EU) | No mandate for structured e-invoicing; PDF only accepted as "electronic invoice" until 31/12/2026, Qualified Electronic Signature (QES) mandatory from 01/01/2027; ATCUD + QR code and SAF-T reporting already mandatory for all invoices | Covered via SAF-T reporting | Autoridade Tributária e Aduaneira (Tax Authority) | – | | Greece | myDATA (AADE) + Peppol (B2G), EN 16931 | Yes, since 2019 | Phased: from 02/03/2026 (large enterprises, >€1m turnover base 2023); from 01/10/2026 (all other VAT-registered businesses) | Covered via myDATA reporting | Code of Tax Procedure (Law 4174/2013), AADE | €1m turnover (base 2023) for phase 1 |

*Overview of Mandates — as of September 2026.*

Germany

XRechnung and ZUGFeRD – both compliant with European standard EN 16931 – have been mandatory in the B2G sector since 27 November 2020. For B2B transactions, the legislature established a phased timeline under the Growth Opportunities Act: since 1 January 2025, all companies must be capable of receiving e-invoices; the issuance mandate takes effect on 1 January 2027 for companies with prior-year turnover exceeding €800,000, and on 1 January 2028 for all remaining businesses. No B2C mandate is planned. The legal basis comprises the Growth Opportunities Act (2024) and EN 16931 within the ViDA framework.

Once the mandate is effective, non-compliance may result in fines of up to €5,000 per violation; buyers also face the risk of losing input VAT deduction if a supplier issues a non-compliant invoice. Invoices must be retained for ten years, counted from the end of the calendar year in which the invoice was issued (GoBD).

Italy

Italy is one of the earliest pioneers, mandating FatturaPA for B2G since 2014/2015 and across all B2B and B2C transactions since 1 January 2019. The foundation is the Sistema di Interscambio (SdI), a centralised clearance platform that validates every invoice before delivery to the recipient. There is no turnover threshold – the requirement applies without exception to all companies.

Late transmission incurs penalties between €250 and €2,000 per invoice; incorrect formatting carries fines of 90 to 180 percent of the VAT amount; non-compliant incoming invoices risk penalties up to 100 percent of VAT. Invoices must be archived for ten years from the tax return submission deadline.

Poland

Poland is introducing a phased B2B mandate using its national XML schema FA(3) via the KSeF platform: companies with annual turnover exceeding PLN 200 million (~€46 million) must comply from 1 February 2026, followed by all remaining businesses on 1 April 2026. A B2C mandate is planned and linked to the B2B framework. The legal basis is the KSeF Act under national VAT legislation.

From 2027, failure to use KSeF can trigger fines of up to 100 percent of the stated VAT, up to 18.7 percent of the gross invoice total if no VAT is stated, and up to PLN 1,000 per delayed transmission; a penalty-free grace period applies through end-2026. The statutory retention period is five years from the end of the tax year.

France

France relies on the hybrid Factur-X format (PDF with embedded XML) as well as UBL and CII standards. Following the B2G mandate in place since 1 January 2020, the obligation to receive e-invoices applies to all companies starting 1 September 2026; large and mid-sized enterprises must also issue e-invoices from that date, with small and micro-enterprises following on 1 September 2027. While there is no separate B2C invoicing mandate, B2C transactions are captured through mandatory e-reporting. The legal foundations are Ordonnance n° 2021-1190 and the Loi de Finances, both aligned with ViDA.

Fines for non-compliant invoices are €50 per invoice (capped at €15,000 per year), and €500 per missing or incorrect e-reporting submission (also capped at €15,000 per year); a grace period has been announced for the launch phase. Invoices must be retained for ten years from the invoice date.

Austria

Austria has required public sector bodies to receive electronic invoices in ebInterface or Peppol BIS 3.0 (CIUS-AT-NAT/GOV) formats since 1 January 2014. For B2B and B2C transactions, however, there is no mandate and none currently announced – adoption remains voluntary. The legal basis is the Federal E-Invoicing Act (ERG).

In the absence of a B2B mandate, there are no specific e-invoicing penalties; general accounting rules under the Federal Fiscal Code (BAO) apply. Invoices must be retained for seven years, or 22 years for real estate-related transactions.

Belgium

Belgium rolled out B2G mandates between November 2022 and November 2023 based on contract value, and since 1 January 2026 requires all VAT-registered businesses to issue and receive electronic invoices via the Peppol network (Peppol BIS). There is no separate B2C mandate. The legal basis is the Law of 6 February 2024 on mandatory e-invoicing; there is no turnover threshold.

Penalties are €1,500 for the first violation, €3,000 for the second, and €5,000 for a third violation within three months; a three-month penalty-free grace period applies until 1 April 2026. Invoices generally must be retained for seven years.

Romania

Romania operates its proprietary national XML format RO e-Factura via the tax authority's (ANAF) centralised clearance system. The B2B mandate took effect in July 2022 for high-risk goods and became general in January 2024; a penalty-free grace period applies to small and medium enterprises until 1 July 2026, based on a €500,000 turnover threshold. A B2C mandate has also been in force since 1 January 2025. The legal basis is Emergency Ordinance (GEO) No. 89/2025 alongside amending regulations.

Late transmission carries fines of RON 1,000 to 2,500 for small businesses and RON 5,000 to 10,000 for large enterprises; non-use of RO e-Factura may incur penalties of 15 percent of the invoice value. Retention requirements are generally ten years.

Danish public sector entities have been mandated to use the OIOUBL format since 2005; migration to Peppol BIS 4 is planned by 2029. There is no general B2B mandate, but from 2026 registration in the NemHandel network becomes the default standard as part of mandatory digital bookkeeping. The legal basis is the Bogføringslov (Bookkeeping Act).

With no B2B mandate, no specific e-invoicing penalties apply; general provisions of the Bogføringslov govern accounting deficiencies. The statutory retention period is five years.

Spain

Spain supports multiple formats in parallel – FacturaE, UBL, CII, and EDIFACT, all compliant with EN 16931. Following the adoption of the implementing regulation on 24 March 2026, the B2B mandate is phased: from 1 October 2027 for companies with annual turnover over €8 million, and from 1 October 2028 for all remaining businesses. While there is no direct B2C invoice mandate, transactions are captured indirectly through status reporting requirements. The legal basis is Article 12 of Law 18/2022 "Crea y Crece" in conjunction with Royal Decree of 24 March 2026.

Under Verifactu, using non-compliant billing software carries fines of up to €50,000 per year for users and up to €150,000 per year for software vendors; general invoice errors are fined at 1 to 2 percent of transaction value, rising to 75 percent in fraud cases. Tax retention is four years (Ley General Tributaria), with commercial law requiring six years in certain cases.

Switzerland, Turkey, and the United Kingdom: Outside the EU Framework

Switzerland has required federal agencies to receive electronic invoices for amounts above CHF 5,000 since 1 January 2016, accepting UBL 2.1, UN/CEFACT CII (eCH-0069 / swissDIGIN), and eBill. No B2B mandate exists at the federal level – adoption is voluntary and decentralised, though individual cantons and municipalities may issue their own rules. The legal basis is federal procurement law. In the absence of a B2B mandate, no specific federal e-invoicing penalties exist; general tax and company law applies to accounting breaches. The statutory retention period is ten years from the end of the financial year.

Turkey has been an established clearance market since 2014 with its e-Fatura system (UBL-TR). From 1 July 2026, registration requirements tighten for businesses with 2025 turnover from TRY 3 million (~€55,600); specific sectors such as e-commerce, real estate, automotive, and hospitality face a lower threshold of TRY 500,000 (~€9,300). Non-registered taxpayers are subject to complementary e-Arşiv rules from 1 January 2026, which also capture B2C sales. The legal basis is General Communiqué No. 509 on the Turkish Tax Procedure Law (Vergi Usul Kanunu). General procedural infractions carry fines of TRY 8,700 to 17,000; special infractions TRY 17,000 to 35,000; repeated document-related violations incur TRY 17,000 or 10 percent of the invoice amount, capped at TRY 17 million annually (2026 figures). The retention period is five years (Vergi Usul Kanunu).

In the United Kingdom, mandatory e-invoicing is currently limited to NHS suppliers. Following a public consultation by HMRC and the Department for Business and Trade, a mandatory rollout based on Peppol BIS 3.0 has been announced for April 2029, subject to confirmation in the 2026 Budget; usage remains voluntary today. Specific thresholds have not yet been defined. Prior to 2029, no e-invoicing-specific penalties apply; standard HMRC rules govern record-keeping defaults. The retention period is six years from the end of the accounting period.

Netherlands

The Netherlands has required the public sector to accept electronic invoices via Peppol since around 2017. A standalone domestic B2B mandate does not yet exist; the EU-wide ViDA requirement for cross-border transactions taking effect on 1 July 2030 will be decisive, with domestic reporting under discussion from 2032 at the earliest. A draft bill is slated for consultation in Q4 2026, with legislation targeted by mid-2028. The legal basis is the EU ViDA Directive and a Ministry of Finance evaluation dated 10 March 2026; no threshold applies yet. Penalties have not been defined pending legislation; general invoice retention is seven years.

Sweden

Sweden has mandated Peppol BIS Billing 3 for the public sector since 1 April 2019, while Svefaktura and EDIFACT are increasingly phased down. No B2B mandate exists yet: an official inquiry launched on 5 February 2026, with a legislative proposal expected by 30 November 2027 aligned with the EU ViDA deadline of 1 July 2030. The legal basis is a Ministry of Finance directive from February 2026 on ViDA implementation; thresholds are to be determined. In the absence of a B2B mandate, no specific penalties apply; general retention is seven years.

Portugal

Portugal mandates e-invoicing for the public sector under EU Directive 2014/55/EU. While there is no mandate for structured B2B e-invoicing, PDF invoices are recognised as "electronic invoices" only until 31 December 2026; from 1 January 2027, a Qualified Electronic Signature (QES) becomes mandatory. The ATCUD code with QR code and SAF-T reporting are already compulsory for all invoices, capturing B2B activity. The regulatory authority is the Portuguese Tax Authority (Autoridade Tributária e Aduaneira); there is no turnover threshold. Penalties follow general tax infraction rules (RGIT) for SAF-T or ATCUD non-compliance; retention is ten years.

Greece

Greece has required public sector e-invoicing since 2019 and relies on the myDATA reporting system from tax authority AADE alongside Peppol for B2G, both compliant with EN 16931. The B2B mandate is phased: starting 2 March 2026 for large enterprises with turnover above €1 million (2023 baseline), and 1 October 2026 for all other VAT-registered businesses. There is no standalone B2C mandate, but consumer sales are reported via myDATA. The legal basis is the Code of Tax Procedure (Law 4174/2013) administered by AADE. Missing or inaccurate reporting incurs fines of €500 to €1,000; taxable transactions carry penalties of 50 percent of VAT; systematic non-compliance can trigger up to €100,000 annually. In B2G, non-compliant invoices may be rejected for payment. Statutory retention is generally five years.

Non-Compliance Penalties & Retention Periods

Penalty details are indicative figures from secondary sources (as of September 2026) and do not constitute legal advice; many penalty schemes take effect only after transitional periods.

| Country | Non-Compliance Penalties (Excerpt) | Retention Period | | --- | --- | --- | | Germany | Fine up to €5,000 per violation (once mandate is effective); risk of input VAT deduction loss on non-compliant vendor invoices | 10 years (GoBD, from end of calendar year of issuance) | | Italy | Late transmission: €250–€2,000 per invoice; wrong format: 90–180% of VAT; non-compliant purchase invoice: up to 100% of VAT | 10 years (from tax return filing deadline) | | Poland (KSeF) | From 2027: up to 100% of stated VAT for non-use of KSeF; up to 18.7% of gross amount if VAT not stated; up to PLN 1,000 per late submission; penalty-free through end-2026 | 5 years (from end of tax year) | | France | €50 per non-compliant invoice (max. €15,000/year); €500 per missing/incorrect e-reporting filing (max. €15,000/year); grace period announced for mandate start | 10 years (from invoice date) | | Austria | No specific e-invoicing penalty (no B2B mandate); general BAO penalties for bookkeeping defaults | 7 years (BAO); 22 years for real estate | | Belgium | 1st offense: €1,500; 2nd offense: €3,000; 3rd offense within 3 months: €5,000; three-month penalty-free grace period until 01/04/2026 | Generally 7 years | | Romania | Late filing: RON 1,000–2,500 (small businesses) to RON 5,000–10,000 (large enterprises); 15% of invoice value for non-use of RO e-Factura | Generally 10 years | | Denmark | No specific e-invoicing penalty (no B2B mandate); general penalties under Bogføringslov for bookkeeping defaults | 5 years | | Spain | Verifactu: up to €50,000/year (users of non-compliant software), up to €150,000/year (software vendors); general invoice errors: 1–2% of transaction value, up to 75% for fraud | 4 years (Ley General Tributaria); commercial law partly 6 years | | Switzerland | No specific e-invoicing penalty at federal level (B2G mandate only); general tax/corporate law for bookkeeping defaults | 10 years (from end of financial year) | | Turkey | General procedural infraction: TRY 8,700–17,000; special procedural infraction: TRY 17,000–35,000; document-related TRY 17,000 or 10% of invoice amount on repeat (annual cap TRY 17m, 2026 figures) | 5 years (Vergi Usul Kanunu) | | UK | No e-invoicing-specific penalty (no mandate before 2029); general HMRC penalties for record-keeping defaults | 6 years (from end of accounting period) | | Netherlands | No specific penalties yet (mandate expected from 2030) | 7 years | | Sweden | No specific penalties yet (no B2B mandate) | 7 years | | Portugal | General tax infraction penalties (RGIT) for SAF-T/ATCUD violations | 10 years | | Greece (myDATA) | €500–€1,000 per missing/incorrect filing; 50% of VAT for taxable transactions; up to €100,000/year for systematic non-compliance; B2G: payment rejection for non-compliance | Generally 5 years |

*Comparison of Penalties and Retention Periods — as of September 2026.*

Context: ViDA as the Common Denominator

Most EU mandates stem from the EU initiative ViDA (VAT in the Digital Age), which establishes a harmonised digital reporting system for cross-border transactions from 1 July 2030 – while domestic obligations remain under national purview. Until then, member states are progressing their B2B mandates at varying speeds: pioneers with established clearance systems like Italy, Poland, and Romania stand alongside countries rolling out full mandates in 2027 or 2028, such as Spain and Germany, or those aligning their timeline with ViDA in 2030, like the Netherlands and Sweden. Switzerland, Turkey, and the UK operate outside EU frameworks: Switzerland limits mandates to B2G, Turkey has run an independent threshold-based model with dedicated penalties since 2014, and the UK plans a decentralised, market-led model from 2029 without a centralised clearance hub.

Across penalty frameworks, many countries – including Poland, Belgium, France, and Romania – have introduced transitional or grace periods where violations are not yet fully penalised. Organisations should leverage this window to implement and stabilise internal systems before statutory fines take full effect.

Practical Recommendations

Beyond format compliance, companies should assess technical connectivity requirements per jurisdiction – such as routing via a Peppol access point or connecting directly to certified national platforms like KSeF, SdI, myDATA, or RO e-Factura.

Additional markets should be evaluated based on business presence, including Croatia, Finland, Ireland, the Czech Republic, or Hungary.

A company-specific impact assessment is essential: which local entities, branch offices, or revenue thresholds trigger early compliance deadlines?

Because key secondary regulations – particularly in Spain, France, Poland, the Netherlands, and Sweden – are still pending final technical specifications or legislative readings, ongoing regulatory monitoring is advised. OXORY helps SAP customers implement country-specific e-invoicing mandates directly within existing billing and SD processes. Contact us to evaluate your international invoicing setup against these statutory deadlines.

Sources

Germany B2B e-Invoicing Mandate: Requirements and Timeline – edicomgroup.com (https://edicomgroup.com/blog/germany-b2b-electronic-invoice)

eInvoicing in Germany – European Commission (https://ec.europa.eu/digital-building-blocks/sites/spaces/DIGITAL/pages/467108886/eInvoicing+in+Germany)

E-Invoicing in Europe 2026: Complete roadmap of mandates and deadlines – fiskaly.com (https://www.fiskaly.com/blog/e-invoicing-mandates-in-europe-2026)

E-invoicing B2B and B2G in Europe Overview – marosavat.com (https://marosavat.com/resources/e-invoicing-in-europe-overview-and-dates)

Turkey's 2026 e-Invoice Deadline Applies to Businesses Exceeding 2025 Turnover Thresholds – fiscal-requirements.com (https://www.fiscal-requirements.com/news/5764-turkeys-2026-e-invoice-deadline-applies-to-businesses-exceeding-2025-turnover-thresholds)

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Mandatory UK e-invoicing for all VAT invoices from 2029: consultation outcome – lexisnexis.com (https://www.lexisnexis.com/en-gb/legal/news/hmrc-dbt-publish-outcome-of-electronic-invoicing-consultation)

The U.K. is introducing mandatory e-invoicing: What businesses need to know – avalara.com (https://www.avalara.com/blog/en/europe/2026/04/uk-mandatory-e-invoicing-2029.html)

Spain: Closer to Mandatory B2B E-Invoicing under Ley Crea y Crece – vatupdate.com (https://www.vatupdate.com/2026/07/07/spain-closer-to-mandatory-b2b-e-invoicing-under-ley-crea-y-crece/)

Romania Extends RO e-Factura (B2B) Deadline for SMEs to 1 July 2026 – meridianglobalservices.com (https://meridianglobalservices.com/romania-extends-ro-e-factura-b2b-deadline-for-smes-to-1-july-2026/)

E-Invoicing in Denmark: Current Requirements and Future Changes – truecommerce.com (https://www.truecommerce.com/blog/e-invoicing-in-denmark-current-requirements-and-future-changes/)

Netherlands Sets 2030 B2B E-Invoicing Mandate, Eyes 2032 Domestic E-Reporting – vatupdate.com (https://www.vatupdate.com/2026/03/16/netherlands-sets-2030-b2b-e-invoicing-mandate-eyes-2032-domestic-e-reporting-aligns-with-eu-vida/)

Sweden Launches Official Inquiry into Mandatory E-Invoicing Implementation – comarch.com (https://www.comarch.com/trade-and-services/data-management/legal-regulation-changes/sweden-launches-official-inquiry-into-mandatory-e-invoicing-implementation/)

E-invoicing in Portugal: Rules, formats, and deadlines for 2026 – fiskaly.com (https://www.fiskaly.com/blog/e-invoicing-in-portugal)

E-Invoicing in Greece: Requirements, Deadlines, and Penalties – vatit.com (https://vatit.com/blog/e-invoicing-in-greece/)

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This article provides general guidance and does not constitute legal or tax advice. Penalty details reflect secondary sources as of September 2026; unfinalised regulations remain subject to legislative adjustments. For individual assessments, an in-depth compliance evaluation is recommended.