> ## Documentation Index > Fetch the complete documentation index at: https://docs.taxrock.com/llms.txt > Use this file to discover all available pages before exploring further. # Look up taxpayer by EIN > Looks up the single business taxpayer with the given EIN and returns its compliance summary. The single-taxpayer counterpart to the client-account lookup. Returns 200 for any well-formed EIN; `result` is null when no accessible business has that EIN. Looks up the single business taxpayer with the given EIN and returns its compliance summary. The single-taxpayer counterpart to the [client-account lookup](/api-reference/client-accounts/lookup-by-ein). Returns `200` for any well-formed EIN. `result` is `null` when no business with that EIN is accessible to you. A missing or malformed `businessEin` returns `400`. Status values, badges, and `tin` censoring are described once in [Concepts → Compliance status](/concepts/compliance-status). ## `result` fields * **`id`, `name`, `type`** — the matched taxpayer (`type` is always `Business` for EIN lookups). * **`tin`, `isTinCensored`** — the business EIN (uncensored for businesses). * **`amountDue`, `unallocatedCredits`** — this taxpayer's balances. `null` while data is pending. * **`numMissingReturns`** — required returns not yet filed, within the recent lookback window. `null` while data is pending. A business still being onboarded (not yet fully provisioned) still matches: it returns `currentStatus.status` of `DataPending` with null financial fields. Use the **Run** panel to try it: paste an access token (see the [Quickstart](/quickstart)) and send a sandbox EIN such as `11-1111111`. ## OpenAPI ````yaml POST /taxpayers/lookup/ein openapi: 3.1.0 info: title: TaxRock Delegate API version: 1.0.0 description: >- Read a TaxRock user's tax-compliance data on that user's behalf, after the user grants consent once. A standard OAuth 2.0 Authorization Code + PKCE integration. See the Guides for the auth flow; the field-level semantics (statuses, badges, TIN censoring) are described in Concepts → Compliance status. servers: - url: https://delegate-demo.api.taxrock.com description: Sandbox - url: https://delegate.api.taxrock.com description: Production security: - bearerAuth: [] paths: /taxpayers/lookup/ein: post: tags: - Taxpayers summary: Look up taxpayer by EIN description: >- Looks up the single business taxpayer with the given EIN and returns its compliance summary. The single-taxpayer counterpart to the client-account lookup. Returns 200 for any well-formed EIN; `result` is null when no accessible business has that EIN. operationId: lookupTaxpayerByEin requestBody: required: true content: application/json: schema: $ref: '#/components/schemas/LookupByEinRequest' responses: '200': description: >- Lookup completed. `result` carries the taxpayer summary, or is null when nothing matched. content: application/json: schema: $ref: '#/components/schemas/TaxpayerLookupResponse' examples: available: summary: Available (data loaded) value: currentStatus: status: NotCompliant badgeGraphicUrl: >- https://taxrock-assets.s3.us-east-2.amazonaws.com/public/status-badges/taxrock-badge-not-compliant.svg result: id: 1a2b3c4d-0000-0000-0000-000000000001 name: Acme Holdings LLC type: Business tin: '111111111' isTinCensored: false amountDue: 18000 unallocatedCredits: 0 numMissingReturns: 1 dataPending: summary: Matched, data not ready value: currentStatus: status: DataPending badgeGraphicUrl: >- https://taxrock-assets.s3.us-east-2.amazonaws.com/public/status-badges/taxrock-badge-data-pending.svg result: id: 2b3c4d5e-0000-0000-0000-000000000002 name: Side Co LLC type: Business tin: '550001111' isTinCensored: false amountDue: null unallocatedCredits: null numMissingReturns: null notMonitored: summary: Not monitored (no taxpayer with that EIN) value: currentStatus: status: NotMonitored badgeGraphicUrl: >- https://taxrock-assets.s3.us-east-2.amazonaws.com/public/status-badges/taxrock-badge-not-monitored.svg result: null '400': description: The `businessEin` was missing or malformed. content: application/json: schema: $ref: '#/components/schemas/ApiError' examples: invalidEin: summary: Malformed EIN value: error: invalid_ein message: >- businessEin must contain nine digits; dashes and spaces are ignored. '401': description: >- Missing or invalid access token. Refresh the token, or send the user back through the authorization flow. '403': description: >- The connected user lacks the required permission. Re-consent will not fix this; treat as a configuration issue. components: schemas: LookupByEinRequest: type: object required: - businessEin properties: businessEin: type: string description: 'Business EIN: nine digits, with dashes and spaces ignored.' examples: - 11-1111111 TaxpayerLookupResponse: type: object required: - currentStatus - result properties: currentStatus: $ref: '#/components/schemas/CurrentStatus' result: anyOf: - $ref: '#/components/schemas/TaxpayerSummary' - type: 'null' description: The taxpayer summary, or null when nothing matched. ApiError: type: object required: - error - message properties: error: type: string description: >- Machine-readable error code, e.g. `invalid_ein` or `invalid_request`. message: type: string description: Human-readable explanation. CurrentStatus: type: object required: - status - badgeGraphicUrl description: >- Compliance status plus an embeddable badge graphic. Always present on a response. properties: status: type: string enum: - NotMonitored - DataPending - Compliant - AtRisk - NotCompliant description: See Concepts → Compliance status for the full meaning of each value. badgeGraphicUrl: type: string format: uri description: >- Publicly hosted SVG badge for this status; embed it directly to display the status. TaxpayerSummary: type: object required: - id - name - type - tin - isTinCensored - amountDue - unallocatedCredits - numMissingReturns properties: id: type: string format: uuid name: type: string type: $ref: '#/components/schemas/TaxpayerType' tin: type: - string - 'null' description: >- Unformatted digits. Raw nine-digit EIN for businesses; censored to the last four for individuals. isTinCensored: type: boolean amountDue: type: - number - 'null' description: Null while data is pending. unallocatedCredits: type: - number - 'null' description: Null while data is pending. numMissingReturns: type: - integer - 'null' description: >- Required returns not yet filed in the recent lookback window. Null while data is pending. TaxpayerType: type: string enum: - Business - Individual description: Whether the taxpayer is a business (EIN) or an individual (SSN). securitySchemes: bearerAuth: type: http scheme: bearer bearerFormat: JWT description: >- The access token obtained from the OAuth flow (see Guides → Quickstart). Paste it here to run the endpoint. ````