# Create certify URL: https://docs.hanzo.ai/docs/openapi/tax/post-tax-profile-certify > Signs the caller org's certification — Form W-9 Part II, Form W-8BEN Part III or Form W-8BEN-E Part XXX — through /v1/legal's e-signature. `POST /v1/tax/profile/certify` > [Tax →](https://docs.hanzo.ai/docs/openapi/tax) · [All API references →](https://docs.hanzo.ai/docs/openapi) · [Get started →](https://docs.hanzo.ai/docs/guides) | | | | ------------- | --------------------------------------------- | | **Address** | `https://api.hanzo.ai/v1/tax/profile/certify` | | **Method** | `POST` | | **Operation** | `post_tax_profile_certify` | | **Auth** | `Authorization: Bearer $HANZO_API_KEY` | Signs the caller org's certification — Form W-9 Part II, Form W-8BEN Part III or Form W-8BEN-E Part XXX — through /v1/legal's e-signature. The org's own admins only, and the admin is the signer: a SuperAdmin acting inside the org is not a person who can certify for it. The first call renders the certification — the IRS's own certification text over this profile's facts, every number truncated — as a /v1/legal document and opens its signature request with the calling admin as signer; the answer is `pending` with the document id. The signer completes it where every /v1/legal signature is completed (POST /v1/legal/documents/{id}/sign/complete). Calling this again then asks legal whether the document is signed and by whom: signed by the signer, the profile is recorded certified; not yet signed, it answers `pending` again; signed by anyone else — another member, a key — or voided, it is not the signer's certification, and a fresh request is opened in its place. A certification covers one profile version: writing any fact on the form afterwards voids it. A certified W-8 is valid through the last day of the third calendar year after the year it was signed (Instructions for Form W-8BEN and W-8BEN-E, Rev. 10-2021); certifying it again after that renews it. It is not a statement that a TIN matches IRS records — that is IRS TIN Matching, which only a payer enrolled in IRS e-Services can run. ## Request The document declares no body for `POST /v1/tax/profile/certify`. The handler is typed in cloud but its shape is not yet emitted, so the fields are not listed here — ask MCP's `describe` for `post_tax_profile_certify`, which answers from the running route. ## Response | Status | Body | Meaning | | --------- | --------------- | ------- | | `200` | tax.Profile | ok | | `default` | problem-details | refused | `200` body — 49 fields. | Field | In | Type | Always | Description | | ------------------------ | ---- | ----------------- | ------ | ------------------------------------------------------------------------------------------------------------------------------------------------------- | | `address` | body | tax.Address | — | | | `address.city` | body | string | — | City is the city or town. | | `address.country` | body | string | — | Country is ISO 3166-1 alpha-2; "US" when absent. | | `address.line1` | body | string | — | Line1 is the number, street, and apartment or suite. | | `address.line2` | body | string | — | Line2 continues the street address, when there is more of it. | | `address.state` | body | string | — | State is the two-letter state or territory code. | | `address.zip` | body | string | — | ZIP is five or nine digits. | | `businessName` | body | string | — | BusinessName is line 2: the business or disregarded entity name. | | `certification` | body | tax.Certification | — | | | `certification.by` | body | string | — | By is who signed it: the IAM user legal recorded completing the signature. | | `certification.document` | body | string | — | Document is the /v1/legal document that carries the signature. | | `certification.signed` | body | integer (int64) | — | Signed is when legal reported the document signed, unix seconds. | | `certification.signer` | body | string | — | Signer is the IAM user the signature was opened for — the admin who asked. | | `certification.status` | body | string | — | Status is none, pending (a signature is open) or certified. | | `certification.version` | body | integer (int64) | — | Version is the profile version the signature covers. | | `classification` | body | string | — | Classification is line 3a. | | `consent` | body | tax.Consent | — | | | `consent.at` | body | integer (int64) | — | At is when the consent was given or withdrawn, unix seconds. | | `consent.by` | body | string | — | By is the IAM user who gave or withdrew it. | | `consent.electronic` | body | boolean | — | Electronic is true while the consent stands. | | `disclosure` | body | string | — | Disclosure is the electronic-delivery disclosure the consent is given against. | | `exemptPayee` | body | string | — | ExemptPayee is line 4's exempt payee code, 1–13. | | `expires` | body | integer (int64) | — | Expires is when a certified W-8 stops being valid, unix seconds: the last day of the third calendar year after the year it was signed. | | `fatca` | body | string | — | FATCA is line 4's FATCA exemption code, A–M. | | `foreignOwners` | body | boolean | — | ForeignOwners is line 3b: a flow-through entity with foreign partners, owners or beneficiaries. | | `foreignTin` | body | string | — | ForeignTIN is a W-8's foreign tax identifying number, masked. | | `form` | body | string | — | Form is w9, w8ben or w8bene. | | `name` | body | string | — | Name is line 1: the name on the income tax return, or of the foreign individual or organization that is the beneficial owner. | | `phone` | body | string | — | Phone is the number a 1099 this org files as PAYER prints for it. | | `tin` | body | string | — | TIN is Part I, masked to its last four digits. | | `tinType` | body | string | — | TINType is which Part I box: ssn (an SSN or ITIN) or ein. | | `updatedAt` | body | integer (int64) | — | UpdatedAt is when the profile last changed, unix seconds. | | `valid` | body | boolean | — | Valid is whether the form establishes what it certifies today — for a W-8, certified for its current version and not expired; for a W-9, a TIN on file. | | `version` | body | integer (int64) | — | Version counts the W-9's revisions; a certification covers exactly one. | | `w8` | body | tax.W8 | — | | | `w8.birth` | body | string | — | Birth is W-8BEN line 8, the individual's date of birth, YYYY-MM-DD. | | `w8.capacity` | body | string | — | Capacity is the capacity in which the signer signs for the beneficial owner — "Director", "Authorized officer". | | `w8.chapter3` | body | string | — | Chapter3 is W-8BEN-E line 4. | | `w8.chapter4` | body | string | — | Chapter4 is W-8BEN-E line 5, the FATCA status. | | `w8.country` | body | string | — | Country is line 2: the country of citizenship (W-8BEN) or of incorporation or organization (W-8BEN-E), ISO 3166-1 alpha-2. | | `w8.giin` | body | string | — | GIIN is W-8BEN-E line 9a, when the chapter 4 status carries one. | | `w8.noForeignTin` | body | boolean | — | NoForeignTIN is W-8BEN line 6b / W-8BEN-E line 9b's alternative: the jurisdiction of residence does not require or issue a foreign TIN. | | `w8.treaty` | body | tax.Treaty | — | | | `w8.treaty.article` | body | string | — | Article is the treaty article and paragraph claimed, e.g. "12(2)". | | `w8.treaty.conditions` | body | string | — | Conditions is the explanation the form asks for: the conditions of the article the beneficial owner meets. | | `w8.treaty.country` | body | string | — | Country is the treaty country the beneficial owner is resident in. | | `w8.treaty.income` | body | string | — | Income is the type of income the claim covers: services, rents, royalties or other. | | `w8.treaty.lob` | body | string | — | LOB is W-8BEN-E line 14b: the treaty's limitation on benefits provision the entity meets. | | `w8.treaty.rateBps` | body | integer (int64) | — | RateBps is the claimed withholding rate in basis points: 0 is exempt, 1000 is 10%. | Failure carries the platform error shape — see [Errors](https://docs.hanzo.ai/docs/errors). ## Examples **CLI** `hanzo` has no subcommand for this operation — the CLI serves only what cloud's live route table confirms. Use HTTP or an SDK. **SDK** **.ts** ```ts import { Configuration, TaxApi } from 'hanzoai'; const api = new TaxApi(new Configuration({ accessToken: process.env.HANZO_API_KEY })); const { data } = await api.postTaxProfileCertify(); ``` **.py** ```python from hanzoai.cloud import ApiClient, Configuration from hanzoai.cloud.api import TaxApi client = ApiClient(Configuration(access_token=os.environ["HANZO_API_KEY"])) result = TaxApi(client).post_tax_profile_certify() ``` **.go** ```go cfg := hanzoai.NewConfiguration() cfg.AddDefaultHeader("Authorization", "Bearer "+os.Getenv("HANZO_API_KEY")) client := hanzoai.NewAPIClient(cfg) resp, _, err := client.TaxAPI.PostTaxProfileCertify(context.Background()).Execute() if err != nil { return err } ``` **.rs** ```rust use hanzo_client::apis::{configuration::Configuration, tax_api}; let mut cfg = Configuration::new(); cfg.bearer_access_token = std::env::var("HANZO_API_KEY").ok(); let result = tax_api::post_tax_profile_certify(&cfg, Default::default()).await?; ``` **.java** ```java import ai.hanzo.cloud.ApiClient; import ai.hanzo.cloud.api.TaxApi; ApiClient client = new ApiClient(); client.setBearerToken(System.getenv("HANZO_API_KEY")); var result = new TaxApi(client).postTaxProfileCertify(); ``` **HTTP** ```bash curl -X POST https://api.hanzo.ai/v1/tax/profile/certify \ -H "Authorization: Bearer $HANZO_API_KEY" ``` **MCP** MCP reaches **tax** through the `tax` tool, which names its 26 operations with its own verbs — this one among them, under a name only MCP declares. `describe` explains any of them: ```bash curl -X POST https://api.hanzo.ai/v1/mcp \ -H "Content-Type: application/json" \ -d '{ "jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": { "name": "describe", "arguments": { "op": "list_tax_filings" } } }' ``` --- [Tax API](https://docs.hanzo.ai/docs/openapi/tax) · [All Hanzo APIs](https://docs.hanzo.ai/docs/openapi) · [Interactive reference](https://docs.hanzo.ai/docs/openapi/reference)