The third DAC7 reporting deadline lands on 31 January 2026, and by now the market has split cleanly in two. Platforms that validate seller TINs at onboarding are exporting files. Platforms that did not are running emergency re-documentation campaigns against sellers who have every incentive to ignore them, under a deadline that does not move.
The arithmetic of bad TINs
Assume a modest 8% invalid-TIN rate across 50,000 sellers: four thousand rejected records, four thousand outreach mails, response rates under half, and a tax authority asking why the same platform fails validation three years running. Multiply by every member state a platform reports into. The cost of a €0.30 validation at signup against this arithmetic is not a close call.
2026 raises the stakes
Tax authorities have stopped treating early cycles as practice: information exchanges between member states are live, mismatch letters are flowing to sellers, and platform-level penalties for systematically poor data are on the table. Meanwhile DAC8 extends the model to crypto-asset providers, importing the same TIN discipline into a new industry.
WeVerify's TIN Verification validates syntax, checksum and, where available, live registry status for personal and company numbers worldwide, one by one at onboarding or millions in batch before filing, with an evidence record for every check.