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You can now verify a TIN + name pair against IRS records.
  • New endpoint: Verify a TIN (POST /tin-match/verify). Send a TIN with a business name, or an individual first and last name. SSNs and EINs both verify. A 200 carries one of three results: Matched, Mismatched, or NotIssued. See TIN verification results for how to read every response.
  • New scope: verify:tins. Existing connections keep working unchanged; to use TIN verification, add verify:tins to your authorize request and have the user re-consent once. See Authentication Details. The Quickstart’s authorize-URL builder has a checkbox for it.
  • Deferrals. Rate limits for this feature are generous, but if they are ever exceeded, you will get a 503 verification_deferred with a Retry-After header. The header is a worst-case estimate; a retry may succeed much sooner.
  • Usage. Every delivered result counts toward the organization’s monthly TIN-verification usage, billed to the TaxRock organization the delegating user belongs to.
  • Sandbox demo data. On the sandbox server, results are deterministic by the TIN’s last four digits, so every response path can be exercised. See the Sandbox testing table.
  • Clearer malformed-request errors on all endpoints: an unparseable or empty request body now returns 400 invalid_request with “Request body is invalid or malformed JSON.”