Navigating Urgent E-Invoicing Mandates: October 2025 Regulatory Alert

October 2025 marked a critical month for e-invoicing compliance, with eight jurisdictions announcing significant regulatory developments.  

As digital transformation accelerates worldwide, businesses must stay ahead of rapidly evolving mandates to maintain operational continuity and mitigate compliance risks. Here are the most important country-specific updates and practical guidance for organisations preparing for change.  

e-Invoicing mandates and jurisdictions

Ireland is adopting a long-term, phased approach to e-invoicing aligned with the EU’s VAT in the Digital Age (ViDA) initiative. On 7 October 2025, the government announced that mandatory domestic B2B e-invoicing will be introduced gradually as part of the 2026 Budget.  

While detailed scope and technical specifications are yet to be released, businesses should begin:  

• Assessing existing invoicing processes  
• Evaluating system readiness for structured electronic invoicing  
• Planning system upgrades and resource allocation  

Action required: early preparation will support a smooth transition and help avoid operational disruption once the phased rollout begins.  

Slovenia has enacted mandatory B2B e-invoicing legislation aligned with the EU's ViDA reforms. From 1 January 2028, all B2B invoices must be electronic and paper invoices will no longer be accepted.  

Key Requirements:  

• Applies to all business entities registered in Slovenia, including natural persons conducting business activity  
• E-invoices must be structured XML documents  
• Decentralised exchange supported through proprietary systems, Peppol network, mini Blagajna platform, and email (for consumer invoicing only)  

Action Required: Businesses should begin planning system upgrades and testing for compatibility with the new framework now to ensure readiness well before the 2028 deadline.  

The European Committee for Standardisation (CEN) ratified significant updates to the EN 16931-1 semantic standard for e-invoicing on 23 October 2025, marking a major step toward harmonising B2B invoice data exchange across the EU.  

The rollout will begin with national announcements in February 2026. This will be followed by the publication and withdrawal of conflicting standards in May 2026, with the final text becoming officially available in November 2026.  

Key Changes:  

• New core semantic data model  
• Updated syntax bindings  
• Enhanced extension methodology to support industry-specific requirements  

Action Required: Businesses operating across multiple EU member states should ensure their systems are compatible with these updates to avoid future compliance gaps.  

Belgium has reaffirmed its commitment to structured electronic invoicing. From 1 January 2026, all invoices issued or sent must comply with structured e-invoice standards.  

Critical Changes:  

• Herrmes platform decommissioned 31 December 2025 - migrate to Peppol-based alternatives via authorised Service Providers  
• Credit-note formats must align with original invoice format  
•  Input VAT deduction requires compliant structured electronic invoice  

Action Required: Review and update invoicing workflows immediately to meet the January 2026 deadline.  

France continues strengthening its e-invoicing landscape. The General Directorate of Public Finances (DGFiP) has extended the mandatory certification deadline for POS and cash-register systems to 1 September 2026, with non-compliance penalties of €7,500 per uncertified system. The Public Invoicing Portal (PPF) qualification environment is now open, requiring registered platforms to complete testing and submit reports by 14 January 2026.  

The draft Finance Law for 2026 establishes a certified platform model for e-invoicing and e-reporting, with increased penalties for invoice errors and reporting failures (first-time or promptly corrected errors exempt).  

Action Required: Ensure POS systems are on track for certification and prepare to register with approved platforms.  

Poland released the KSeF 2.0 API Demo environment on 15 October 2025, enabling businesses to test integration of financial and ERP systems under production-like conditions.  

The demo environment allows companies to identify integration gaps, verify compatibility, and adjust processes.  

Action Required: Begin testing now to avoid last-minute complications and ensure readiness for future compliance deadlines.  

Germany's domestic B2B e-invoicing mandate is now in force, with a transitional period running until 31 December 2027.  

The mandate covers all domestic B2B transactions between German-established businesses, requires EN 16931-compliant structured e-invoices, and no longer requires recipient consent.  

Key Requirements:  

• All mandatory invoice details must be included within the structured file  
• Original e-invoice must be archived for audit purposes  
• Recurring invoices and corrections must be processed through structured electronic invoices referencing the original document  
• Validation tools strongly recommended to ensure compliance  

Action Required: Ensure invoicing systems are EN 16931-compliant and implement robust validation processes before the transitional period ends.  

Outside of Europe, The Philippines has extended the e-invoicing compliance deadline to 31 December 2026. Currently obligated taxpayers include those engaged in e-commerce, those under the Large Taxpayers Service, and users of Computerised Accounting Systems, with future expansion planned for additional groups including exporters and POS users.  

Action Required: Upgrade accounting systems and monitor regulatory updates closely to ensure timely compliance.  

What These Changes Mean for Your Business  

 October's regulatory developments underscore the urgency of proactive e-invoicing compliance. Organisations should prioritise:  

• System Audits: Evaluate current invoicing capabilities against new requirements  
• e-Invoicing Solution Provider Engagement: Work with technology partners to plan upgrades and migrations  
• Staff Training: Ensure teams understand new processes and compliance obligations  
• Phased Implementation: Prepare for transitional periods and staged rollouts  
• Ongoing Monitoring: Stay informed of evolving regulations and technical specifications  

Next Steps  

Don't let regulatory changes disrupt your business operations. Vertex provides comprehensive e-invoicing solutions and expert guidance to help you navigate complex compliance requirements across multiple jurisdictions. Get in touch.