E-invoice validator: Peppol BIS Billing 3.0 and EN 16931
Upload a UBL or CII e-invoice: the validator checks its format, applies the official rules of the European standard EN 16931 and of Peppol BIS Billing 3.0, and reviews the key invoice data. Free, instant, and the file is not stored.
UBL or CII XML file, or PDF with embedded XML (Factur-X / ZUGFeRD), 4 MB maximum
What the validator checks
Today, an Irish business may invoice electronically, including by PDF, with the prior agreement of its customer. Public bodies must receive and process e-invoices that comply with the European standard EN 16931 (S.I. 258/2019), and Peppol BIS Billing 3.0 is the format used in the Irish public sector.
Revenue plans structured e-invoices for large corporates from November 2028, with every business able to receive them. Revenue states that the format will comply with EN 16931 and that a PDF will not be enough. This timeline is a plan, not yet a law, and the technical specifications have not been published.
The validator reads the file, recognises its syntax (UBL or CII) and profile, then applies the official rule sets: EN 16931 (mandatory data, calculations, code lists) and, for UBL invoices, the Peppol BIS Billing 3.0 rules published by OpenPeppol. A CII invoice is checked against EN 16931 only, because Peppol BIS Billing 3.0 uses UBL.
It also checks the invoice number and date, the seller's VAT number, the due date and the consistency of the net, VAT and gross amounts. Each point is explained, with how to fix it. The file is analysed in memory and not stored.
- Compliant: the check passed.
- To review: nothing blocking, but a point deserves your attention.
- Error: the invoice breaks an official rule and should be corrected before it is sent.
- The validator is not a certification: your Peppol access point and your customer run their own checks.
Official sources
- OpenPeppol — Peppol BIS Billing 3.0
- OpenPeppol — Peppol BIS Billing 3.0 rules for UBL
- Irish Statute Book — S.I. No. 258 of 2019, Electronic Invoicing in Public Procurement
- European Commission — eInvoicing in Ireland
- Revenue — Other types of VAT invoices (electronic invoices)
- Revenue — Implementation of eInvoicing in Ireland (PDF)
Rules checked on 20 October 2026. Free tool for information only: it is not legal or tax advice. The rules are checked against the official sources listed on this page; check your own situation before acting.
Frequently asked questions
Is a PDF invoice still valid in Ireland?
Yes, with your customer's prior agreement to receive invoices electronically. Revenue's plan would require structured e-invoices from November 2028 for large corporates, but it is not a law yet.
Which files can I check?
A UBL or CII XML file, or a PDF with embedded XML (Factur-X / ZUGFeRD), up to 4 MB. A plain PDF is reported as not being a structured e-invoice.
Why is my CII invoice not checked against Peppol rules?
Peppol BIS Billing 3.0 is defined in UBL. A CII invoice is checked against the European standard EN 16931 only.
Is my file stored?
No. It is analysed in memory and then discarded. If you ask for the report by email, only the invoice data needed to rebuild the report is sent, then discarded too.
What do codes like BR-CO-15 or PEPPOL-EN16931-R001 mean?
They are the identifiers of the official rules: BR-… rules come from EN 16931, PEPPOL-… rules from Peppol BIS Billing 3.0. Give them to your software provider: they say exactly what to fix.
Further reading
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