Peppol mandatory from 2026: what potential pitfalls should you be aware of?
February 2026 - Since 1 January 2026, electronic invoicing via Peppol has been the norm for all B2B invoices between Belgian VAT-registered companies. Although there is a grace period until the end of March 2026, the legal framework is set. What potential pitfalls lie ahead?
For many SME managers, this means more than just a new obligation: it is a fundamental change in the way invoices are sent, received and tracked. No more PDFs in the mailbox, no paper documents and no separate Excel files. Anyone who considers Peppol to be merely a technical formality underestimates its impact on day-to-day operations.
Be alert for “invisible” invoices
Peppol ensures standardised and secure exchange of invoices between software systems. This improves data quality and reduces manual input, but it also means that invoices no longer arrive “visibly” as they used to. They appear directly in an application. For companies that do not know where to look, this can lead to uncertainty and missed payments. Especially in the first few months after implementation, closer monitoring of outstanding invoices is no luxury.
Avoid lost invoices and late payments
One of the most common risks is the feeling that invoices disappear. Not because they haven't been sent, but because they end up in a new system. When customers don't notice that a new invoice is ready, payment is delayed.
In November and December 2025, software developer Teamleader analysed the payment behaviour of nearly 750,000 outgoing invoices, approximately a quarter of which were sent via Peppol. It was striking that e-invoices were paid more slowly than invoices sent by e-mail, with no clear difference between larger and smaller companies. Specifically, in December 2025, non-Peppol invoices were paid after 10 days on average, while e-invoices via Peppol took an average of 14 days. In November, Peppol invoices were even settled after 20 days on average.
This problem is mainly organisational. Entrepreneurs need to know which tool they are using, where notifications appear and who is responsible for follow-up. Clear internal agreements and a quick check after the first Peppol transactions can prevent a lot of frustration.
Break with old habits
During the transition phase, many companies continue to stick to familiar routines. As a precaution, they also send Peppol invoices by email or as PDFs. This may seem safe, but it has the opposite effect: duplicate documents, extra checks and a greater risk of errors in the accounts. Once Peppol is up and running, a single channel is sufficient. More communication channels do not mean greater security, but greater complexity.
No full automation
Another pitfall is the expectation that Peppol will automatically handle the entire accounting process. Although the data arrives in a structured format, checks, approvals and substantive decisions are still necessary. An electronic invoice does not mean automatic approval or payment. Companies retain the right to dispute invoices, and payments still go through the usual channels. So set realistic expectations to avoid disappointment.
Build certainty into sending and receiving
Many SMEs assume that they are “on Peppol”, without knowing exactly whether their registration is fully active. The status of sent invoices is also not always clear. Has the invoice actually been sent? Has it been received? This uncertainty can lead to stress and late payments. Transparency about the status of invoices and confirmation of receipt is therefore a basic requirement when choosing software.
More tools, more complexity
Peppol simplifies the exchange of invoices, but does not solve the fragmentation of software. On the contrary: SMEs often work with multiple applications for invoicing, accounting, payments and reporting. Without an overview, there is a risk of inefficiency. It is important for business leaders to make choices that are scalable and that keep collaboration with external partners, such as accountants, simple.
Administrative impact of invoicing errors
In a Peppol environment, corrections are strictly made via credit notes. An incorrect invoice cannot simply be replaced. This increases the administrative impact of errors, especially when the corrections are also incorrect. Clear invoicing processes and additional checks at source are therefore more important than ever. The fewer errors there are beforehand, the less corrective work is needed afterwards.
