TL;DR: E-invoicing in Europe is becoming mandatory country by country, and Slovakia, Spain and the UK each use a different model:
Slovakia (1 January 2027): Mandatory B2B and B2G e-invoicing via Peppol, with near real-time reporting to the tax authority. Businesses within the receiving obligation must be ready to accept e-invoices. A proposed fine-free period until June 2027 does not delay the deadline.
Spain (6 October 2027 / 2028): The countdown started on 6 October 2026. Companies with turnover above EUR 8 million go first, all others a year later. Invoice status and payment data must also be reported.
UK (1 April 2029): Peppol will be the core interoperability framework for VAT e-invoicing. Detailed requirements are expected by April 2028; future digital reporting is a separate consultation.
What to do now: Map your entities and invoice flows, start with Slovakia, and choose one multi-country platform instead of a separate tool for each mandate. Melasoft and Docnova help coordinate country-specific requirements through one multi-country setup.
Europe e-invoicing is moving from optional to mandatory at speed. Belgium switched on mandatory B2B e-invoicing in January 2026, France followed in September 2026, and Germany’s first issuing obligations start in January 2027. This autumn brought three more important e-invoicing updates in Europe: Slovakia’s go-live is approaching, Spain has fixed its implementation dates, and the UK has published its implementation roadmap.
The three share the same goal but use three different models. For companies working across borders, that is the real challenge behind European e-invoicing mandates: one approach rarely fits every country.
Slovakia E-Invoicing: Live from 1 January 2027
Slovakia is the most urgent of the three. Under Act No. 385/2025, Slovak VAT payers must issue structured e-invoices for domestic B2B and B2G transactions from 1 January 2027, and practically every business established in Slovakia must be able to receive them, even without a VAT registration.
Slovakia e-invoicing runs on a Peppol-based five-corner model. Invoices are exchanged in EN 16931 format (Peppol BIS Billing 3.0) between certified service providers, often called “digital postmen”, and the invoice data is reported to the Financial Administration in near real time as part of the same flow. The Slovak tax ID (DIČ) is the key identifier on the network. This matters for groups with several sites, because only one Peppol registration per tax ID is possible.
Parliamentary Print 1454 proposes a six-month transition period for specified penalties and changes to buyer-side invoice reporting. These proposals should not be treated as a postponement of the 1 January 2027 obligation. Companies should check the final enacted text and the Financial Administration’s latest instructions before configuring their reporting and exception processes.
Spain E-Invoicing: The Countdown Has Started
Spain e-invoicing has been discussed since the Crea y Crece law of 2022, but its implementation countdown was only triggered in October 2026. Royal Decree 238/2026 set the rules in March, and Order HAC/1028/2026, which defines the technical requirements for the public platform, entered into force on 6 October 2026. That started the clock:
- 6 October 2027: companies with annual turnover above EUR 8 million
- 6 October 2028: all other companies and self-employed professionals
The Spanish Tax Agency (AEAT) must make its free public e-invoicing solution available by 6 August 2027. Companies can use it or connect through private platforms. Spain also requires companies to report invoice status and payment information, because a key aim of the law is to reduce late payments. The mandate covers in-scope domestic B2B transactions, subject to the statutory exceptions.
Do not confuse it with Verifactu, the separate rules for invoicing software. Its scope and implementation timetable need to be assessed separately from the B2B e-invoicing reform; companies should not assume that an exemption under one regime removes obligations under the other.
UK E-Invoicing: The 2029 Roadmap Is Here
UK e-invoicing took a big step forward on 28 October 2026, when HMRC published its roadmap alongside the Budget. From 1 April 2029, the government intends to require VAT-registered persons, including public bodies, to issue and receive VAT invoices as e-invoices, subject to exemptions. A PDF or Word document alone is not a structured e-invoice. The detailed scope, including exclusions and implementation rules, will be confirmed before launch.
The UK has chosen Peppol as its core interoperability framework, with HMRC taking the role of UK Peppol Authority. Digital reporting is a separate policy question: HMRC has opened a consultation on whether invoice data should be reported in the future, without deciding that such reporting will be introduced.
A technical consultation is planned for spring 2027. The government aims to confirm key requirements between October 2027 and April 2028, with software-provider readiness testing from summer 2028. Business identifiers remain part of the design work. Existing EDI arrangements may continue alongside the future framework, but users will also need to be capable of interoperable e-invoice exchange.
Three Countries, Three Models
The overview below shows why a single approach rarely works across European invoice regulations:
| Requirement | Slovakia | Spain | United Kingdom |
|---|---|---|---|
| Go-live | 1 January 2027 | 6 October 2027 (turnover above EUR 8m), 6 October 2028 (all others) | 1 April 2029 |
| Model | Peppol five-corner | Public AEAT solution plus private platforms | Peppol interoperability framework |
| Reporting to tax authority | Near real time, with each invoice | Invoice status and payment data | Separate digital-reporting consultation; no decision to introduce it |
| Scope | Domestic B2B and B2G | Domestic B2B | B2B and B2G VAT invoices |
| Transition | Fine-free period to June 2027 proposed | Two phases by turnover | Detailed rules due by April 2028 |
What Companies Should Do Now for E-Invoicing Compliance in Europe
Start by mapping every entity, VAT registration and invoice flow per country, outgoing and incoming. Then work through the upcoming e-invoicing mandates in order of urgency:
- Slovakia: choose a certified provider now and run full end-to-end tests before January. Keep purchase-invoice reporting in your plans until the amendment is adopted.
- Spain: companies in the first phase should plan ahead of October 2027. Plan ERP changes, invoice status reporting and, where relevant, Verifactu together.
- UK: use the time until 2028 to clean up customer and supplier master data and check that your systems can send and receive via Peppol.
Finally, avoid a separate tool for each mandate. B2B e-invoicing in Europe is converging on Peppol and EN 16931, and from July 2030 the EU’s ViDA package extends it to intra-EU transactions. A multi-country platform can reduce repeated integration work, while still applying each country’s specific requirements.
How Melasoft and Docnova Help
Melasoft supports companies with e-invoicing, e-reporting and SAF-T compliance in more than 30 European markets. Companies running SAP can use the Melasoft SAP Add-On to create, send and receive compliant e-invoices directly from SAP ECC or SAP S/4HANA, with outbound and inbound cockpits inside SAP. For other ERP systems, or for companies that prefer a cloud solution, Docnova connects via API, SFTP or a simple web portal.
Melasoft is a certified Peppol Access Point and is accredited in Slovakia, where it is listed on the official register of certified providers. Slovak e-invoicing and the statutory reporting therefore run through one connection. The same Peppol infrastructure is the foundation the UK has chosen for 2029.
Conclusion
Europe e-invoicing is no longer a distant topic. Slovakia goes live on 1 January 2027, Spain’s countdown is running, and the UK has set out a path to April 2029. Companies that plan across countries today will avoid rushed projects tomorrow.
Want to check where your business stands? Talk to the Melasoft team, start with Docnova for free, or join one of our e-invoicing webinars.
Sources: Spain: Order HAC/1028/2026; UK: HMRC implementation roadmap; UK: digital reporting consultation; Slovakia: Financial Administration eFaktúra guidance.