UBL/XML Validation for Peppol
Bring your invoice output into compliance with Peppol BIS 3.0 and EN16931. We fix the schematron violations, country profile mismatches, and long-tail edge cases that break in production.
- Package
- UBL/XML Validation
- Price
- From €8,000
- Notes
- Fixed scope. Fixed price. Final price depends on country profile coverage and invoice volume.
Who this is for. And who it isn't for.
Good fit
- Finance and ERP teams whose invoices are getting rejected or returned by receivers and access points.
- Companies expanding from one country profile (e.g. XRechnung) into additional Peppol markets like Belgium or the Netherlands.
- Organisations that pass test validation but see failures in production with real invoice data.
- Teams preparing for go-live that need a clean compliance baseline across all document types.
Not a fit
- Companies that have not yet mapped their invoice data to UBL. Start with a Readiness Assessment.
- Teams looking for a one-click validator tool. Our free Peppol Validator handles that.
- Organisations that only send domestic invoices within a single, stable country profile.
Deliverables. What you get.
Schematron audit
Rule-by-rule audit of your invoice output against EN16931 business rules and Peppol BIS 3.0 schematron. Every violation documented with root cause and fix path.
Country profile coverage
Validation against each country profile in scope. Belgian e-FFF, XRechnung, NLCIUS, Factur-X, and others. Cross-country mismatches surfaced and resolved.
Validation Report
Full report with pass/fail/warning for every rule checked. Grouped by rule set, annotated with severity and remediation guidance. The deliverable you hand to your ERP team.
Fix implementation
We work with your ERP team to implement fixes. Mapping corrections, tax breakdown adjustments, attachment encoding, and credit-note edge cases. Not just a report. Fixes that land in production.
Regression test suite
Test suite covering all document types and country profiles in scope. Re-run after fixes to confirm compliance. Handed over so your team can run it on future changes.
Case study. German manufacturer expanding into Belgian and Dutch e-invoicing.
Anonymised customer profile. Names and figures changed. Company details available on request under NDA.
The situation
A German Mittelstand manufacturer with around 250 staff has been sending XRechnung invoices to German public-sector customers for two years. The process works. But rejection rates have been climbing as the country profile validation rules tighten with each schematron update.
The head of finance and the ERP lead share ownership of the initiative. The company plans to extend e-invoicing to B2B customers and expand into Belgian and Dutch markets. Both countries require Peppol BIS 3.0 compliance with their own country profile extensions. The current XRechnung output has never been tested against those profiles.
What commonly goes sideways
For a profile like this, the most common issues we would surface in the validation audit include:
- Tax breakdown rejections
- Cross-country rejections cluster around the BR-CO-15 family of tax breakdown rules. The German profile tolerates certain rounding approaches that the Belgian profile rejects outright. Multi-rate invoices are the worst offenders.
- PDF attachment encoding
- PDF-attachment embedding that works for XRechnung breaks Peppol BIS in production. The MIME type encoding accepted by German receivers is rejected by the Peppol BIS 3.0 schematron when the same invoice targets Belgian or Dutch receivers.
- Credit note edge cases
- Long-tail credit-note edge cases never caught in test. Negative amount handling, tax rounding on partial credits, and multi-line credit notes with mixed VAT rates all surface only with real production data.
- Country profile gaps
- Fields required by the Belgian e-FFF profile (such as TaxRepresentativeParty for non-BE sellers) are absent from the XRechnung output. The ERP mapping was built for a single country and has no awareness of multi-profile requirements.
What a UBL/XML Validation engagement covers for this profile
In a validation engagement for this profile we would collect production invoice samples across all document types: standard invoices, credit notes, and self-billing documents. We run every sample against the full EN16931 business rule set, the Peppol BIS 3.0 schematron, and each country profile in scope.
The Validation Report documents every violation with root cause and severity. We then work with the ERP team to implement fixes. Tax breakdown recalculations, attachment MIME type corrections, credit-note rounding adjustments, and country-profile-specific field additions. Every fix is re-validated before sign-off.
The engagement ends with a regression test suite that covers all document types and country profiles. The team can re-run it on future ERP changes or schematron updates. No dependency on us for ongoing compliance checks.
Indicative outcomes
- reissue and rejection volume cut within 4 weeks
- ~80%
- Systematic fix of the top violation families eliminates the bulk of rejections. Remaining cases addressed in regression testing.
- rejection-driven AR delay reduced
- 8–15 days
- Every rejected invoice restarts the AR clock. Eliminating rejections recovers cash flow that was stuck in the reissue-and-wait cycle.
- manual re-issuing workload eliminated
- ~70%
- Finance staff currently re-keying and re-sending rejected invoices. Fixing the root cause removes the manual loop entirely for the addressed violation classes.
Sample deliverable
Not sure where your rejections come from?
15 minutes with a senior e-invoicing expert. Walk through your rejection patterns and get an honest recommendation on whether a validation engagement is the right next step.
Hosted by Tom Van Asbroeck
Peppol & tax expert
Process. How we run it.
Week 1
Kickoff and sample collection
Align on country profiles in scope, document types, and known rejection patterns. Collect production invoice samples across all ERP outputs.
Week 1–2
Full validation audit
Run every sample against EN16931 business rules, Peppol BIS 3.0 schematron, and applicable country profiles. Document every violation with root cause analysis.
Week 2–3
Validation Report delivery
Deliver the full Validation Report. Walk through findings with finance and ERP teams. Prioritise fixes by severity and business impact.
Week 3–5
Fix implementation
Work alongside your ERP team to implement mapping corrections, tax breakdown fixes, attachment encoding changes, and credit-note adjustments.
Week 5–6
Regression testing and handover
Re-run the full test suite against corrected output. Confirm compliance across all profiles. Hand over the regression suite for ongoing use.
Investment. Format and pricing.
From €8,000
Fixed scope. Fixed price. Final price depends on country profile coverage and invoice volume.
Related packages
Often followed by
ImplementationImplementation
End-to-end pipeline setup. Peppol registration, format mapping, ERP integration, test cycles, and supervised go-live.
Often starts with
Readiness AssessmentReadiness Assessment
Gap analysis of your ERP, formats, and processes against applicable mandates. Includes a Peppol Readiness Scan.
FAQ. Frequently asked questions.
Do you fix the issues or just report them?
Which country profiles do you cover?
Our invoices pass the free validator. Why do we still get rejections?
How is this different from running your free Peppol Validator?
Can you work with our ERP vendor directly?
How long does the engagement take?
Discuss on a discovery call.
30 minutes with a co-founder or senior e-invoicing expert. You leave the call with a clear next step. Tailored proposal in your inbox within 48 hours.
Vendor-neutral. No obligation to switch platforms.
Hosted by Tom Van Asbroeck
Peppol & tax expert