How does TIN matching behave in sandbox?

Sandbox never contacts the IRS. Every TIN result comes from the seeded test case your search matched, so the behavior is predictable but only for the names and TINs on the test case list.

Business searches

• Search a seeded test business with the TIN from its test case and tin_matched comes back with that case’s value.

• Search a seeded test business with any other TIN, or with no TIN, and tin_matched is null. This is not an outage; sandbox simply has no IRS result for that input.

• Search a real business or a real EIN and nothing matches. Sandbox inputs must match a test case, and real-world data is not in the sandbox.

To test the outage-and-retry flow, search Ampro Industries Inc at 6465 N Quail Hollow Rd Ste 200, Memphis TN 38120 with the TIN 000000000. The search completes with tin_matched null, then a few seconds later it flips to true and a BusinessSearch.updated webhook is sent, exactly as production does after the IRS recovers.

Standalone TIN verifications

POST /tin_verifications works in sandbox with any name. The TIN 123456789 returns tin_matched true; any other TIN returns false. The submitted and completed webhooks fire the same way they do in production, and nothing is billed.