Automating invoicing in Europe is not the same as automating invoicing in the US. EU VAT law imposes specific requirements on invoice content, numbering, and processing. Get them wrong and you risk a VAT audit, disallowed input credits, or penalties. Get them right and you have a system that generates, sends, tracks, and reconciles invoices with minimal human intervention.
EU VAT Directive Article 226: mandatory invoice fields
Every VAT invoice issued by an EU business must contain specific fields defined in Article 226 of the EU VAT Directive. Missing any of them means the invoice may be rejected by your customer's tax authority, which means they can't claim the input VAT credit — which means they'll ask you to re-issue it.
The mandatory fields are: (1) sequential invoice number with no gaps, (2) invoice date, (3) tax point date if different from invoice date, (4) supplier's full name and address, (5) supplier's VAT registration number, (6) buyer's full name and address, (7) buyer's VAT number (for B2B transactions), (8) description of goods or services supplied, (9) quantity and unit price, (10) VAT rate applied, (11) total VAT amount, (12) total amount payable including VAT, (13) for intra-EU supplies: a reference to the applicable provision and a note that the supply is exempt or zero-rated.
VIES validation: checking cross-border VAT numbers
For intra-EU B2B transactions, you must verify that your customer's VAT number is valid at the time of supply. The VIES (VAT Information Exchange System) is the EU's official database for this check. An invalid or expired VAT number means you cannot zero-rate the transaction — you must charge local VAT instead.
Automating VIES checks at the point of invoice creation — before the invoice is issued — eliminates this risk. If the number is invalid, the system flags it for manual review rather than generating a non-compliant invoice.
Sequential invoice numbering: no gaps permitted
EU VAT law requires that invoice numbers form an unbroken sequence. A gap in your invoice sequence — even a single missing number — is a red flag in a VAT audit. The auditor will ask why the gap exists. If you can't explain it, they may assume it was a sale you failed to declare.
Practically, this means your invoicing system must own the number sequence. You cannot let invoice numbers be generated by multiple systems or assigned manually. The sequence must be atomic: each new invoice gets the next number, with no possibility of collision or skipping.
Common formats by country: Poland uses FV/YEAR/NR (e.g., FV/2026/001), Czech Republic uses YEAR/NR (e.g., 2026/001), Germany typically uses a custom prefix with a sequential counter.
Country-specific tax IDs
Each EU member state has its own tax identification format alongside the EU VAT number:
Poland: NIP (Numer Identyfikacji Podatkowej) — 10 digits, format XXX-XXX-XX-XX Czech Republic: DIČ (Daňové identifikační číslo) — prefix CZ + 8–10 digits Slovakia: DIČ — prefix SK + 10 digits Hungary: Adószám — 11 digits Germany: Steuernummer — varies by state, typically 10–11 digits Austria: UID — prefix ATU + 8 digits
For Polish companies, the NIP is required on all domestic invoices in addition to the VAT number. Your invoicing system must accommodate these country-specific fields.
SEPA payment automation: IBAN, BIC, and payment references
Once an invoice is issued, the next step is getting paid. SEPA (Single Euro Payments Area) covers 36 countries and enables euro-denominated bank transfers that settle within 1–3 business days (or same-day with SEPA Instant Credit Transfer).
For automated payment processing, your invoice must include: the supplier's IBAN, the supplier's BIC/SWIFT code, a unique payment reference that allows automatic matching when the payment arrives, and the due date.
The payment reference is critical for reconciliation. A structured reference (following the ISO 11649 creditor reference format) can be parsed automatically by your bank's systems. An unstructured reference requires more sophisticated matching logic.
MT940 and CAMT.053: automatic bank reconciliation
European banks provide transaction data in standardised formats that enable automatic reconciliation. MT940 is the older SWIFT format, still widely used by Central European banks. CAMT.053 is the newer ISO 20022 XML format, increasingly required by banks under PSD2.
Both formats contain: the transaction amount, value date, description, and — critically — the payment reference. An automated reconciliation system reads the incoming bank statement, matches transactions to open invoices using the payment reference, and marks invoices as paid. Transactions that can't be matched automatically are queued for manual review.
For a business issuing 100–500 invoices per month, automatic reconciliation saves 5–15 hours of accounting work per month.
Credit notes under EU law
When you need to cancel or adjust an invoice, EU law requires a formal credit note — not a deleted invoice. The credit note must reference the original invoice number, state the reason for the adjustment, and be issued with its own sequential number in the credit note series.
Critically, you cannot delete an invoice from your records. Both the original invoice and the credit note must be retained for the statutory period (7–10 years depending on the member state).
How DAICISION handles this end-to-end
DAICISION's finance module covers the full EU invoice lifecycle: Article 226-compliant invoice generation with all mandatory fields, automatic VIES validation at invoice creation, atomic sequential invoice numbering per tenant with configurable format patterns, SEPA payment details on all invoices (IBAN + BIC), MT940 and CAMT.053 import for automatic bank reconciliation, credit note generation with original invoice reference, and 10-year document retention with audit trail.
Country-specific fields (NIP for Poland, DIČ for Czech/Slovakia, etc.) are supported as configurable tenant settings, not hardcoded — because your business model shouldn't require a code change to operate in a new market.