Comply with Spain Veri*factu invoicing requirements via the AEAT web service

Steps

1. Confirm your applicability date: corporate taxpayers must comply from 1 January 2027; self-employed individuals with economic activity from 1 July 2027 — earlier 2026 deadlines referenced in older documentation have been postponed by one year.
2. Register your billing software or access point with AEAT and obtain the technical specifications for the Veri*factu submission web service from the AEAT developer portal.
3. For each invoice, generate a chaining hash (huella) by applying SHA-256 to specified fields of the previous invoice in the series, producing a tamper-evident chain; include this hash and the previous invoice's timestamp in the current record.
4. Submit invoice records to AEAT in real-time or in batches using the AEAT web service for billing records (Article 15) or verifiable invoice records (Article 16.1); real-time submission posts each record immediately after issuance.
5. Embed a QR code on every invoice visualization that encodes the AEAT verification URL; also print the phrase confirming the invoice is verifiable on the AEAT website.
6. Test all flows in the AEAT pre-production sandbox environment before enabling production submission.