API Endpoint: Company Name Lookup by EIN

The company-name-lookup-by-ein endpoint returns the registered business name associated with an EIN.

POST /api/v1/validate/company-name-lookup-by-ein

https://www.tincomply.com/api/v1/validate/company-name-lookup-by-ein

Submit an EIN and get back the registered business name associated with it. Useful when a vendor supplies an EIN but not the exact legal name.

Request body

FieldTypeDescription
tinrequired string The EIN to look up. 9 digits; hyphens are ignored.

Response object: companyNameLookupByEinResult

FieldTypeDescription
namestringThe registered business name.
foundboolTrue when a name was found for the EIN.
messagestringHuman-readable summary of the result.
completedboolFalse when the upstream source was unavailable. The request is retried automatically; call request-details with the request id later to get the finished result.

What to do with this result

When you seeDo this
found is trueCompare name with the name your vendor gave you. If they differ, ask for the legal name and run IRS TIN matching with it.
found is falseNo name is on record for this EIN in our sources, which does not prove it is invalid. Run IRS TIN matching with the name the payee supplied.
completed is falseThe source was unavailable. Keep the request id and call request-details later; the result fills in once the retry succeeds.

Sample request

curl -X POST https://www.tincomply.com/api/v1/validate/company-name-lookup-by-ein \
  -H "X-API-Key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"tin":"13-0871985"}'

Sample response

{
  "id": "Yk2pW8sQnE6cRtV1aZbLm0Xo",
  "request": {
    "tin": "XXXXX1985",
    "requestDate": "2026-10-01T14:02:11Z",
    "requestedServices": "company-name-lookup-by-ein"
  },
  "companyNameLookupByEinResult": {
    "name": "INTERNATIONAL BUSINESS MACHINES CORPORATION",
    "message": "EIN lookup match found",
    "found": true,
    "completed": true
  }
}

Errors

Requests that cannot be processed return HTTP 400 with an object keyed by field name, each listing what was wrong. Authentication, permission and other status codes are covered in Errors & service status.

This endpoint requires an API key with the Validate permission.

See how this check works in the portal and what it costs: EIN & Company Lookup