What a mandate actually requires
An e-invoicing mandate does not mean sending a nicer PDF. It means three things. First, the invoice becomes a structured data file, usually XML, that machines read. A PDF is a picture of an invoice; a structured invoice is the invoice itself. Most national formats are based on the European standard EN 16931. Second, the invoice travels through a defined channel rather than your email. That is either a government platform, as in Poland and Italy, or the Peppol network, as in Belgium, or accredited private providers, as in France. Third, the moment of delivery changes. In clearance models the invoice is legally delivered when the platform accepts it and assigns an identifier, not when your customer opens the message.
Where mandates are live or coming
| Country | Date | Who | Channel and format |
| Italy | since 2019 | all B2B | SdI platform, FatturaPA |
| Romania | since July 2024 | all B2B | RO e-Factura |
| Belgium | 1 January 2026 | all B2B at once | Peppol network, Peppol BIS 3.0 |
| Poland | 1 February 2026 above PLN 200m turnover, 1 April 2026 most others, 1 January 2027 smallest sellers | B2B | KSeF platform, FA(3) XML |
| France | 1 September 2026 receiving for all and issuing for large and mid-sized companies, 1 September 2027 for SMEs | B2B | accredited providers, Factur-X and UBL |
| Slovakia | 1 January 2027 | B2B | national rules |
| Germany | receiving since 1 January 2025, issuing from 1 January 2027 above EUR 800,000 turnover, all businesses 1 January 2028 | B2B | XRechnung, ZUGFeRD |
| EU (ViDA) | 1 July 2030 | intra-EU B2B | structured e-invoices and digital reporting |
Does this apply to your store?
Do you sell to businesses? Mandates cover B2B. If every order goes to a consumer, none of these rules force you to change how you invoice, though you still need correct VAT invoices where local law requires them.
Where are you established? The obligation follows the seller’s country, not the customer’s. A German store selling to Belgium follows German rules for its own invoices, and must be able to receive Belgian ones.
What is your turnover? Germany and France phase obligations by company size. Poland has an exception for the smallest sellers until the end of 2026. Belgium does not: every business started on the same day.
What changes inside WooCommerce
Your store already collects most of the data these formats need, but not all of it, and not always in a usable state.
- Buyer identification. Structured invoices require the buyer’s VAT number for B2B transactions, and some networks also need a Peppol participant identifier. If your checkout has no VAT number field, add one and validate it.
- Complete addresses. Free-text address fields cause rejections. Country, city and postal code have to be present and correctly mapped.
- Tax rates that match reality. Zero-rated sales, reverse charge and exemptions all need explicit codes. A rate of 0% with no reason attached will fail validation in several countries.
- Invoice numbering. Once invoices pass through a platform, gaps and duplicates become visible. Sequential, uninterrupted numbering matters more than before.
- Corrections. Credit notes follow the same route as invoices. Ad hoc corrections in a spreadsheet stop being an option.
What to do this quarter
- Confirm your deadline by country of establishment, and check whether you are in the first or a later phase.
- Decide how invoices will leave your store: through your invoicing plugin, your accounting software, or a service provider connected to the required network.
- Add and validate VAT numbers at checkout, and mark B2B orders clearly.
- Clean up tax rate configuration, including reverse charge and exempt sales.
- Test with real orders before the deadline, including a correction, a foreign customer and a mixed-rate order.
- Agree with your accountant who monitors rejected invoices and fixes them.
Where Flexible Invoices fits
Flexible Invoices issues VAT invoices, proformas and corrections from WooCommerce orders, validates EU VAT numbers in VIES, handles reverse charge and OSS, and sends documents automatically. That covers the invoicing layer: correct data, correct documents, correct numbering.
For the structured file itself, the PEPPOL for Flexible Invoices PRO add-on generates invoices in the Peppol standard and lets you download ready-to-use UBL (XML) files straight from the invoice edit screen. Transmission over a network still goes through an access point provider, and platforms such as KSeF have their own channel.
Flexible Invoices is free to start with. PRO costs EUR 59 a year for one site, and the All Plugins Bundle costs EUR 99 a year for 25 sites and includes every add-on, PEPPOL included, with priority support.
Get your invoice data ready before your deadline. Flexible Invoices PRO issues compliant invoices from every WooCommerce order, and the PEPPOL add-on turns them into UBL files. Try the free version first, then upgrade when your mandate date is set. 30-day money-back guarantee.
