International E-Invoicing: Country-by-Country Legal Requirements

Why Looking Beyond Germany Matters

Electronic invoicing across large parts of Europe is no longer a future topic, but an active or imminent obligation. While individual countries like Italy or Romania have relied on central clearance systems for years, others – such as Germany or Spain – are only at the beginning of a phased rollout. The driving force behind most European initiatives is the EU reform ViDA (VAT in the Digital Age), which ultimately aims for an EU-wide harmonized digital reporting system. Until then: regulated nationally, divergent nationally – with noticeable consequences for businesses operating internationally. We have already covered the German e-invoicing mandate and the fundamentals of ViDA in dedicated articles; here is the country-by-country overview for the largest economic areas inside and outside the EU.

Mandates at a Glance

The following overview summarizes formats, mandates, legal frameworks, and thresholds by country. Detailed analyses for each country follow in the sections below.

| Country | Format / Standard | B2G Mandate | B2B Mandate | B2C Mandate | Legal Basis | Threshold | | --- | --- | --- | --- | --- | --- | --- | | Germany | XRechnung, ZUGFeRD (EN 16931-compliant) | Yes, since Nov 27, 2020 | Phased: Receipt from Jan 1, 2025 (all); Issuance from Jan 1, 2027 (>€800,000 turnover); from Jan 1, 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 Jan 1, 2019 | Yes, since Jan 1, 2019 | National law; central clearance system Sistema di Interscambio (SdI) | None – applies to all businesses | | Poland | FA(3) / KSeF (national XML schema) | – | Phased: from Feb 1, 2026 (>PLN 200M ≈ €46M); from Apr 1, 2026 (all remaining) | Planned, linked to B2B | KSeF Act (national VAT law) | PLN 200M (~€46M) for Phase 1 | | France | Factur-X (hybrid PDF+XML), UBL, CII | Yes, since Jan 1, 2020 | Phased: Receipt from Sep 1, 2026 (all); Issuance from Sep 1, 2026 (large/medium enterprises); from Sep 1, 2027 (SMEs/microenterprises) | Via e-reporting obligation (linked to B2B) | Ordonnance n° 2021-1190 / Loi de Finances; EU-ViDA-compliant | Phased by enterprise size | | Austria | ebInterface, Peppol BIS 3.0, CIUS-AT-NAT/GOV | Yes, since Jan 1, 2014 | No – voluntary, no mandate announced | No | Federal E-Invoicing Act (ERG) | – | | Belgium | Peppol BIS (mandatory via Peppol network) | Yes, phased Nov 2022–Nov 2023 (by contract value) | Yes, since Jan 1, 2026 (issuance & receipt) | No | Act of Feb 6, 2024 on mandatory e-invoicing | None – all VAT-registered businesses | | Romania | RO e-Factura (national XML) | Yes | Yes, since July 2022 (high fiscal risk goods) / January 2024 (general); SME grace period (penalty-free) until July 1, 2026 | Yes, since Jan 1, 2025 | GEO No. 89/2025 et al. amending ordinances; central clearance system (ANAF) | €500,000 turnover (SME grace period) | | Denmark | OIOUBL (transition to Peppol BIS 4 planned by 2029) | Yes, since 2005 | No – no general B2B mandate; from 2026 automatic NemHandel registration as default under digital bookkeeping obligations | No | Bookkeeping Act (Bogføringslov) | – | | Spain | FacturaE, UBL, CII, EDIFACT (EN 16931) | Yes, since 2015 | Phased: from Oct 1, 2027 (>€8M turnover); from Oct 1, 2028 (all remaining) – Royal Decree adopted on Mar 24, 2026 | Indirectly covered via status reporting obligation | Law 18/2022 "Crea y Crece" Art. 12; Real Decreto of Mar 24, 2026 | €8M annual turnover for Phase 1 | | Switzerland | UBL 2.1 / UN/CEFACT CII (eCH-0069 / swissDIGIN), eBill | Yes, since Jan 1, 2016 (Federal Administration) | No – no federal B2B mandate, voluntary/decentralized; 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: e-Fatura registration required from July 1, 2026 for businesses with 2025 turnover ≥ TRY 3M (special threshold TRY 500k for e-commerce, real estate, automotive, hospitality); from Jan 1, 2026 e-Arşiv mandatory for all unregistered taxpayers | Covered via e-Arşiv | General Communiqué No. 509 on Tax Procedure Law (Vergi Usul Kanunu) | TRY 3M (~€55,600); TRY 500k (~€9,300) sector-specific | | United Kingdom (UK) | Peppol BIS 3.0 | Yes (NHS suppliers) | Announced from April 2029 (subject to confirmation in 2026 Budget); currently voluntary | Not planned | Consultation "Promoting electronic invoicing across UK businesses and the public sector" (HMRC/DBT) | Still open | | Netherlands | Peppol BIS, EN 16931 | Yes (since approx. 2017, via Peppol) | No mandate yet – cross-border from July 1, 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 (Mar 10, 2026) | – | | Sweden | Peppol BIS Billing 3 (Svefaktura/EDIFACT increasingly restricted) | Yes, since Apr 1, 2019 | No mandate yet – official inquiry running since Feb 5, 2026, legislative proposal expected by Nov 30, 2027, aligning with EU-ViDA deadline July 1, 2030 | No | Ministry of Finance directive (Feb 2026) on ViDA implementation | Still open | | Portugal | CIUS-PT (EN 16931 / UBL 2.1) | Yes (EU Directive 2014/55/EU) | No mandate for structured e-invoices; PDF accepted as "electronic invoice" only until Dec 31, 2026, Qualified Electronic Signature (QES) mandatory from Jan 1, 2027; ATCUD + QR code and SAF-T reporting already mandatory for all invoices | Covered via SAF-T reporting obligation | Portuguese Tax and Customs Authority (Autoridade Tributária e Aduaneira) | – | | Greece | myDATA (AADE) + Peppol (B2G), EN 16931 | Yes, since 2019 | Phased: from Mar 2, 2026 (large enterprises, >€1M turnover based on 2023); from Oct 1, 2026 (all remaining VAT-registered businesses) | Covered via myDATA reporting obligation | Code of Tax Procedure (Law 4174/2013), AADE | €1M turnover (2023 baseline) 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 B2G transactions since November 27, 2020. For B2B transactions, the legislature introduced a phased roadmap via the Growth Opportunities Act: Since January 1, 2025, all enterprises must be able to receive electronic invoices; mandatory issuance takes effect on January 1, 2027, initially for businesses with prior-year turnover exceeding €800,000, and on January 1, 2028, for all remaining companies. A B2C mandate is not planned. The legal basis is the 2024 Growth Opportunities Act alongside EN 16931 within the context of ViDA.

Once the mandate takes full effect, non-compliance penalties can reach up to €5,000 per violation; additionally, input tax deduction may be jeopardized if the supplier provides a non-compliant invoice. Invoices must be retained for ten years, starting from the end of the calendar year in which the invoice was issued (GoBD).

Italy

Italy is among the pioneers and has mandated electronic invoicing via FatturaPA since 2014/2015 in the B2G sector and since January 1, 2019 across the board for B2B and B2C transactions. The system is built on the Sistema di Interscambio (SdI), a central clearance platform through which every invoice is verified prior to delivery to the recipient. No turnover threshold applies – the mandate applies universally to all enterprises.

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

Poland

Poland is implementing a phased B2B mandate using the national XML schema FA(3) via the KSeF platform: Enterprises with turnover exceeding PLN 200 million (approx. €46 million) must comply starting February 1, 2026, with all other enterprises following on April 1, 2026. A B2C mandate is linked to the B2B rules and is currently in planning. The legal basis is the KSeF Act within national VAT legislation.

From 2027 onwards, failure to use KSeF incurs penalties of up to 100 percent of the stated VAT, up to 18.7 percent of the gross amount if VAT is not stated, and up to PLN 1,000 per late submission; a penalty-free grace period applies through the end of 2026. The retention period is five years from the end of the tax year.

France

France relies on the hybrid format Factur-X (PDF with embedded XML) as well as the UBL and CII standards. Following the B2G mandate in place since January 1, 2020, mandatory e-invoice receipt applies to all enterprises starting September 1, 2026; large and medium-sized enterprises must also begin issuing on the same date, with small and micro-enterprises following on September 1, 2027. While no standalone B2C invoicing mandate exists, B2C transactions are effectively covered by the accompanying e-reporting requirement. The legal basis rests on Ordonnance n° 2021-1190 and the Loi de Finances, both aligned with ViDA.

Non-compliant invoices face penalties of €50 per invoice (capped at €15,000 per year), while missing or incorrect e-reporting submissions incur €500 per occurrence (also capped at €15,000 per year); a grace period has been announced for the launch phase. Invoices must be archived for ten years from the invoice date.

Austria

Austria has required public sector entities to receive electronic invoices in ebInterface or Peppol BIS 3.0 formats (CIUS-AT-NAT/GOV) since January 1, 2014. For B2B and B2C transactions, however, there is no mandate and no announced timeline – adoption remains voluntary. The legal basis is the Federal E-Invoicing Act (ERG).

Due to the absence of a B2B mandate, there are no specific e-invoicing penalties; general accounting compliance provisions of the Federal Fiscal Code (BAO) apply. The retention period is seven years, extending to 22 years for real estate transactions.

Belgium

Belgium phased in its B2G mandate between November 2022 and November 2023 based on contract value, and as of January 1, 2026, mandates all VAT-registered enterprises to issue and receive electronic invoices via the Peppol network (Peppol BIS). There is no separate B2C mandate. The legal framework is the Act of February 6, 2024 on mandatory e-invoicing; no turnover threshold applies.

Fines are €1,500 for the first violation, €3,000 for the second, and €5,000 for the third violation within three months; a three-month penalty-free transition period applies until April 1, 2026. The standard retention period is seven years.

Romania

Romania utilizes RO e-Factura, a national XML format, operating through the central clearance platform of the tax authority ANAF. The B2B mandate was introduced in July 2022 for high fiscal risk products and expanded generally in January 2024; small and medium-sized enterprises benefit from a penalty-free transitional window until July 1, 2026, based on a €500,000 turnover threshold. Additionally, a B2C mandate has been in force since January 1, 2025. The legal basis is Emergency Ordinance (GEO) No. 89/2025 along with amending decrees.

Late submissions trigger fines of RON 1,000 to 2,500 for smaller companies and RON 5,000 to 10,000 for large enterprises; bypassing RO e-Factura entirely can result in penalties of 15 percent of the invoice value. The statutory retention period is generally ten years.

Denmark

Denmark has required the public sector to use the OIOUBL format since 2005, with a transition to Peppol BIS 4 planned by 2029. There is no general B2B mandate; however, starting in 2026, registration in the NemHandel network becomes the default standard as part of digital bookkeeping compliance. The legal framework is the Bookkeeping Act (Bogføringslov).

In the absence of a B2B mandate, there are no e-invoicing-specific penalties; standard accounting penalties under the Bogføringslov apply. The retention period is five years.

Spain

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

Under the Verifactu framework, using non-compliant billing software risks fines of up to €50,000 per year for users and up to €150,000 per year for software developers; general invoicing infractions are penalized at 1 to 2 percent of transaction value, rising up to 75 percent in fraud cases. The tax retention period is four years (Ley General Tributaria), though commercial code requirements may mandate six years.

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

Switzerland has required the Federal Administration to receive electronic invoices for amounts above CHF 5,000 since January 1, 2016, utilizing UBL 2.1, UN/CEFACT CII (eCH-0069 / swissDIGIN), and eBill. There is no B2B mandate at the federal level – adoption remains voluntary and decentralized, though individual cantons and municipalities may enforce local rules. The legal basis is federal procurement law. There are no federal e-invoicing penalties due to the lack of a B2B mandate; general corporate and tax law applies to accounting breaches. The retention period is ten years from the close of the financial year.

Turkey is an established clearance market, operating the e-Fatura system (UBL-TR) since 2014. From July 1, 2026, the mandatory registration threshold is lowered for enterprises with 2025 turnover of TRY 3 million (approx. €55,600) and above; selected industries such as e-commerce, real estate, motor vehicle trading, and hospitality face a lower threshold of TRY 500,000 (approx. €9,300). Unregistered taxpayers are subject to the complementary e-Arşiv system starting January 1, 2026, which also captures 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 procedural infractions TRY 17,000 to 35,000, and repeated document-related violations TRY 17,000 or 10 percent of the invoice value, capped at TRY 17 million per year (2026 figures). The retention period is five years (Vergi Usul Kanunu).

In the United Kingdom, e-invoicing is currently only mandatory for suppliers to the National Health Service (NHS). 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; adoption remains voluntary for now. Specific turnover thresholds have not yet been defined. Prior to 2029, no e-invoicing-specific penalties exist; general HMRC rules apply for bookkeeping errors. The retention period is six years from the end of the accounting period.

Netherlands

The Netherlands has required public sector electronic invoicing via Peppol since approximately 2017. A standalone domestic B2B mandate is not yet in place; the primary milestone is the EU-wide ViDA mandate for cross-border transactions effective July 1, 2030, with domestic reporting under discussion for 2032 at the earliest. A draft bill is slated for consultation in Q4 2026, with legislation targeted for mid-2028. The legal foundation is the EU ViDA Directive alongside a Ministry of Finance evaluation dated March 10, 2026; no thresholds have been established yet. Penalties are not yet determined in the absence of a mandate; the general retention period is seven years.

Sweden

Sweden has mandated public sector e-invoicing under Peppol BIS Billing 3 since April 1, 2019, while Svefaktura and EDIFACT are increasingly restricted. A B2B mandate does not yet exist: An official inquiry has been underway since February 5, 2026, with a legislative proposal expected by November 30, 2027, aligned with the EU ViDA deadline of July 1, 2030. The legal basis is a Ministry of Finance directive from February 2026 on ViDA implementation; thresholds are pending. No specific penalties exist prior to a B2B mandate; the standard retention period is seven years.

Portugal

Portugal mandates public sector e-invoicing based on EU Directive 2014/55/EU. While there is no structured B2B e-invoicing mandate, PDF invoices are only recognized as "electronic invoices" until December 31, 2026; starting January 1, 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 transactions. The legal basis is governed by the Portuguese Tax and Customs Authority (Autoridade Tributária e Aduaneira); no specific turnover threshold applies. Penalties follow standard tax infraction laws (RGIT) for SAF-T or ATCUD non-compliance; the retention period is ten years.

Greece

Greece has mandated public sector e-invoicing since 2019 and utilizes the myDATA reporting system by the AADE tax authority for B2B transactions, combined with Peppol for B2G, both compliant with EN 16931. The B2B mandate is phased: from March 2, 2026 for large enterprises with turnover above €1 million (based on 2023 figures), and from October 1, 2026 for all remaining VAT-registered businesses. There is no separate B2C mandate, but consumer sales are captured through myDATA reporting. The legal framework is the Greek Code of Tax Procedure (Law 4174/2013) via AADE. Incorrect or missing transmissions incur fines of €500 to €1,000, taxable transactions risk 50 percent of the VAT amount, and systematic non-compliance can result in up to €100,000 annually; in B2G scenarios, non-compliant invoices can be rejected for payment. The retention period is generally five years.

Non-Compliance Penalties & Retention Periods

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

| Country | Non-Compliance Penalties (Excerpt) | Retention Period | | --- | --- | --- | | Germany | Fines up to €5,000 per violation (once mandate is effective); risk of input tax deduction denial for non-compliant supplier invoices | 10 years (GoBD, from end of calendar year of invoice issuance) | | Italy | Late transmission: €250–€2,000 per invoice; incorrect format: 90–180% of VAT; non-compliant incoming invoice: up to 100% of VAT | 10 years (from tax return filing deadline) | | Poland (KSeF) | From 2027: up to 100% of stated VAT for failure to use KSeF; up to 18.7% of gross amount if VAT not shown; up to PLN 1,000 per late submission; penalty-free through end of 2026 | 5 years (from end of tax year) | | France | €50 per non-compliant invoice (max. €15,000/year); €500 per missing/incorrect e-reporting submission (max. €15,000/year); grace period announced for launch phase | 10 years (from invoice date) | | Austria | No specific e-invoicing penalties (no B2B mandate); general BAO penalties for bookkeeping deficiencies | 7 years (BAO); 22 years for real estate transactions | | Belgium | 1st violation: €1,500; 2nd violation: €3,000; 3rd violation within 3 months: €5,000; 3-month penalty-free grace period until Apr 1, 2026 | Generally 7 years | | Romania | Late submission: RON 1,000–2,500 (small business) to RON 5,000–10,000 (large enterprise); 15% of invoice value for failure to use RO e-Factura | Generally 10 years | | Denmark | No specific e-invoicing penalty (lack of B2B mandate); general penalties under Bogføringslov for bookkeeping deficiencies | 5 years | | Spain | Verifactu: up to €50,000/year (users of non-compliant software), up to €150,000/year (software providers); general invoicing errors: 1–2% of transaction value, up to 75% for fraud | 4 years (Ley General Tributaria); partly 6 years under commercial law | | Switzerland | No specific e-invoicing penalties at federal level (B2G only); general tax/corporate law for bookkeeping deficiencies | 10 years (from end of fiscal year) | | Turkey | General procedural: TRY 8,700–17,000; special procedural: TRY 17,000–35,000; document-related: TRY 17,000 or 10% of invoice amount upon repetition (annual cap TRY 17M, 2026 values) | 5 years (Vergi Usul Kanunu) | | UK | No e-invoicing-specific penalties (no mandate before 2029); general HMRC penalties for bookkeeping errors | 6 years (from end of accounting period) | | Netherlands | No specific penalties yet (mandate starting 2030) | 7 years | | Sweden | No specific penalties yet (no B2B mandate) | 7 years | | Portugal | General tax infringement fines (RGIT) for SAF-T/ATCUD violations | 10 years | | Greece (myDATA) | €500–€1,000 per incorrect/missing submission; 50% of VAT for taxable transactions; up to €100,000/year for systematic non-compliance; B2G: payment refusal 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 derive from the EU initiative ViDA (VAT in the Digital Age), which establishes an EU-wide harmonized digital reporting system for cross-border transactions starting July 1, 2030 – purely domestic mandates remain a national prerogative. Until then, member states regulate B2B requirements nationally and at varying speeds: Early adopters with established clearance systems like Italy, Poland, and Romania contrast with late adopters whose mandates take full effect in 2027 or 2028, such as Spain and Germany, or those implementing mandates strictly in line with ViDA by 2030, like the Netherlands and Sweden. Switzerland, Turkey, and the United Kingdom operate outside the EU framework: Switzerland limits itself strictly to B2G mandates, Turkey has maintained an independent, threshold-based clearance system with distinct penalties via e-Fatura since 2014, and the UK plans a decentralized, market-driven model without a central clearance platform starting in 2029.

Regarding penalties, many countries – including Poland, Belgium, France, and Romania – deliberately operate with transitional grace periods during which violations are not penalized or penalized leniently. Businesses should use this window to execute internal transitions before full penalty structures take effect.

Practical Recommendations

Beyond pure format compliance, organizations should thoroughly evaluate technical connectivity per country, such as Peppol access points or country-specific certified platforms like KSeF, SdI, myDATA, or RO e-Factura.

Additional countries should be assessed based on your business footprint, such as Croatia, Finland, Ireland, the Czech Republic, or Hungary.

A corporate exposure assessment is essential: Where do subsidiaries or turnover thresholds trigger early mandate compliance?

Because several regulations – including those in Spain, France, Poland, the Netherlands, and Sweden – are still finalizing technical implementation rules or draft legislation, continuous monitoring of ongoing developments is strongly advised. OXORY helps SAP users implement country-specific e-invoicing mandates directly within existing billing processes. Get in touch with us to review your international billing operations against these 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)

E-invoicing compliance in Switzerland – ecosio.com (https://ecosio.com/en/compliance/switzerland/e-invoicing/)

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/)

E-Invoice Retention Periods: A Global Compliance Guide – originstamp.com (https://originstamp.com/en/blog/reader/e-invoice-retention-periods-by-country)

E-Invoicing Non-Compliance Penalties by Country – invoicenavigator.eu (https://www.invoicenavigator.eu/answers/e-invoicing-non-compliance-penalty)

France: E-invoices and E-reporting penalties – meridianglobalservices.com (https://meridianglobalservices.com/france-e-invoices-and-e-reporting-penalties/)

Zakres obowiązkowego KSeF (Scope of mandatory KSeF) – ksef.podatki.gov.pl (https://ksef.podatki.gov.pl/informacje-ogolne-ksef-20/zakres-obowiazkowego-ksef/)

Verifactu Spain 2026: Dates, Who Must Comply & Fines – getrenn.com (https://static.getrenn.com/blog/verifactu)

Romania's Latest E-Invoicing Rules: Additional Details and Fines Published – fonoa.com (https://www.fonoa.com/resources/blog/romanias-latest-e-invoicing-rules-additional-details-and-fines-published)

State treasury in Spain clarifies invoice retention period to avoid penalties – fiscal-requirements.com (https://www.fiscal-requirements.com/news/3924)

e-Faturaya Geçmeme Cezası – uyumsoft.com (https://www.uyumsoft.com/blog/e-faturaya-gecmeme-cezasi)

This article is provided for introductory guidance and does not constitute legal advice. Penalty values represent indicative information from secondary sources (as of September 2026); regulations that have not yet been formally adopted remain subject to change. For a definitive assessment in specific corporate cases, we recommend a detailed compliance review.