Peppol Confirmed as the UK's Core E-Invoicing Network

What HMRC confirmed on 23 June 2026

On 23 June 2026, HM Revenue and Customs published Tax update 2026: simplification, modernisation and fairness. In it, the government confirmed that Peppol, the electronic procurement system, will be the core interoperability network for e-invoicing in the UK. HMRC presented this as an indication of the direction of travel towards the e-invoicing mandate planned for 2029, intended to let software developers and businesses begin planning their products and their rollout. The government also said it will continue to engage with stakeholders on the role of legacy systems that cannot interoperate with the future system.

This article stays with what official sources confirm: the UK government's own publications, and the official material on Belgium from the European Commission and the Belgian tax authority. Belgium is the most directly comparable market to have switched on a Peppol-based business-to-business mandate. Where the detail is not yet settled, that is flagged rather than filled in.

What is confirmed about the UK regime

Drawing on the HMRC and Department for Business and Trade consultation response published in November 2025, the position as it stands is as follows.

The mandate covers all VAT invoices from 2029. This was announced at Budget 2025. The government notes that VAT invoices are typically issued for business-to-business and business-to-government transactions where VAT is due, and not for business-to-consumer transactions.

The model is decentralised. The government has focused its work on a decentralised model, in which businesses exchange e-invoices directly through their chosen software providers, rather than a centralised model that routes every invoice through a government platform of the kind used in Italy. The government confirmed that this position did not change after the consultation, and 63% of respondents agreed it was the right focus.

Real-time reporting is not part of the 2029 mandate. The government will consider some form of real-time reporting at a later date, once e-invoicing is well established, but has been explicit that it will not be introduced alongside the 2029 mandate.

The roadmap and standards come at Budget 2026. An implementation roadmap is due to be published at Budget 2026. The detailed technical standards are still to be developed, and the government has said it will work with stakeholders to weigh adopting an existing standard against designing a UK-specific one. A period of detailed stakeholder collaboration began in January 2026.

Parts of the public sector already use Peppol. All bodies covered by the Public Procurement Act 2023 are required to accept e-invoices that comply with BS EN 16931, and NHS Supply Chain requires its suppliers to issue e-invoices through the Peppol network.

What Peppol is, in the government's own terms

The consultation response glossary describes Peppol as a global network for the standardised exchange of electronic business documents. It describes the four-corner model, a term it attributes to Peppol, as a model in which businesses exchange e-invoices through their service providers, allowing for interoperability and flexibility. The government notes that Peppol is being used in many EU countries and more widely, including in Singapore, Malaysia and Australia. The European Commission similarly describes Peppol as a secure, standardised network that allows businesses and public authorities to exchange documents such as invoices in a structured and interoperable way.

Belgium: a live, decentralised Peppol mandate

The European Commission's country factsheet sets out the Belgian position. Belgium adopted a decentralised Peppol model, and business-to-business e-invoicing became mandatory from 1 January 2026 for VAT-liable transactions between VAT-liable entities, covering approximately 1.2 million entities. Sending a PDF invoice by email or via a platform is no longer enough.

Under the Belgian rules, Peppol is the primary format and transmission method. Alternative formats may be used only where both parties agree and the alternative can be converted to EN 16931, and the default Peppol route must always remain possible. To support organisations that were not yet able to receive structured invoices in the run-up to the mandate, Belgium ran a temporary platform, Hermes, that converted structured e-invoices into a readable format such as PDF. Having judged the private market mature enough, the Belgian government decommissioned Hermes on 31 December 2025, the day before the mandate began, with access to archived invoices ending on 31 March 2026.

Belgium's first months also carry a practical lesson. The obligation is two-sided: a business must be able to both send and receive structured invoices through Peppol, so being set up only to send is not enough. To ease the start, the Belgian tax authority allowed a period of tolerance for the first three months of 2026, waiving penalties for businesses that could show they had taken timely and reasonable steps to comply. That window has now closed, and any penalty depends on the specific circumstances of the case.

One point is directly relevant to UK planning. Belgium intends to add a near real-time VAT reporting layer in 2028, which will replace the existing annual client listing. The Commission notes that this system will again use the Peppol framework, which limits the impact on businesses already connected for e-invoicing. In other words, the official record indicates that getting connected for e-invoicing first reduces the additional work when a reporting layer is added later.

Why the UK chose a mandate rather than encouragement

The UK government's consultation response is candid about the evidence behind its choice. It notes that Singapore, New Zealand and Australia promoted e-invoicing and set clear standards but operated voluntary business-to-business models, with Singapore and New Zealand now moving towards mandates for some transactions. It then states that the government's own research into other jurisdictions found that regimes without a mandate have generally not achieved significant uptake, despite, in several cases, a strong regulatory framework for interoperability and significant government effort to encourage adoption. The response adds that, in some voluntary regimes, businesses reported having to run both e-invoicing and conventional invoicing because some of their customers would not accept e-invoices, which discouraged adoption. This is the official basis for the UK's decision to mandate, in order to reach the level of uptake at which network effects appear.

The benefits the government is relying on

The consultation response sets out the benefits the policy is built on, citing industry research. It states that e-invoicing has the potential to cut invoicing costs by between 60% and 80%. It cites research evidencing a 20% reduction in late payments on adoption, an annual saving of around £11,300 for small firms, a 3% boost to labour productivity in finance-heavy sectors, and a 2.2 times return on investment for small firms over two years. Separately, the response cites figures published by New Zealand's Ministry of Business, Innovation and Employment indicating that processing an e-invoice costs around 38% of the cost of processing a paper invoice and around 43% of the cost of processing a PDF invoice.

How to plan, based on the official timeline

The single most useful date is Budget 2026, when the roadmap and the technical standards are due. Budget 2026 is the government's autumn fiscal event, expected in autumn 2026, with the exact date yet to be confirmed by HM Treasury. Detailed stakeholder engagement began in January 2026. Following those publications is the substance of preparation in the near term, because the formal requirements flow from them.

The lead-in time is deliberately long. The consultation response notes that a consistent theme from respondents, and from firms operating in jurisdictions that already have mandates, was the need for clear guidance and sufficient lead time, and that this shaped the decision to set the mandate for 2029. Respondents' own implementation estimates varied widely. Many businesses, from micro to large, thought they could implement within a year, and the majority of those suggested around six months, while a few smaller firms with low awareness thought it could take five years or more. Awareness is the variable, so understanding the requirements as they emerge is the main task now.

The known difficulties are worth preparing for. Respondents to the consultation highlighted the challenge of integrating e-invoicing with existing ERP and legacy systems, the problem of different formats across systems, and the importance of structured data fields such as VAT numbers and invoice numbers. Reviewing how your current systems and data would support structured invoicing is therefore sensible groundwork, and is consistent with the Belgian experience that businesses already connected face less work when later requirements arrive.

Choosing a provider in light of your existing systems

The official position offers a few practical anchors, though it stops short of a provider checklist.

The decentralised model is designed so that businesses can choose a service provider that suits them. The government's stated aim is that, with the right standards, whichever provider a business selects, it will be able to issue and receive e-invoices when trading with any other UK VAT-registered business.

Several Making Tax Digital providers focused on the small business market already offer e-invoicing services, and the government expects the market to provide a range of low-cost, easy-to-use solutions, as it did for Making Tax Digital. For many businesses, then, the first step is simply to ask whether their existing accounting or Making Tax Digital software will support e-invoicing, and what the provider's plans are.

Integration with existing accounting and ERP systems was one of the most consistently raised considerations, and integration with legacy infrastructure was flagged as a significant challenge. That points towards favouring a solution that fits your current finance systems rather than one run separately alongside them.

The government has also noted that some closed invoicing networks and portals lock suppliers into a particular provider, and that interoperability regardless of provider is a core aim of the regime. That is worth keeping in mind when assessing any platform. Accountants and bookkeepers are expected to play a key role in supporting adoption, so professional advisers are a reasonable first point of contact.

One caveat, in the interest of accuracy: the detailed UK standards and the shape of the regime are still to be set out at and after Budget 2026. Final, provider-specific requirements will become clearer then, so decisions taken now are best kept flexible. Our UK e-invoicing guide tracks the requirements as they are confirmed.

The bottom line

Confirming Peppol as the UK's core interoperability network settles which network the 2029 mandate will be built around. The model is decentralised, real-time reporting is not part of the initial mandate, and the implementation roadmap and standards are due at Budget 2026, with stakeholder engagement having begun in January 2026. The international record, drawn from official sources, supports the government's central claims, that e-invoicing reduces costs and late payments, and that voluntary approaches have struggled to reach the adoption a mandate provides. The practical work between now and 2029 is to follow the standards as they are published, review how your current systems and data would support structured invoicing, and confirm your software provider's plans.

Sources

HM Revenue and Customs, Tax update 2026: simplification, modernisation and fairness summary, published 23 June 2026 (gov.uk).

HM Revenue and Customs and Department for Business and Trade, Promoting electronic invoicing across UK businesses and the public sector: consultation response, updated 26 November 2025 (gov.uk).

European Commission, eInvoicing in Belgium, Digital Building Blocks country factsheet.

FPS Finance, the Belgian federal tax authority, Period of tolerance during the first three months of 2026 (einvoice.belgium.be).

New Zealand Ministry of Business, Innovation and Employment, benefits of e-invoicing, as cited in the UK consultation response.