# Remove a tax ID from a customer

> The customers.tax_ids.delete operation: DELETE /api/v1/customers/{id}/tax_ids/{taxIdId} in the REST API and the customers_tax_ids_delete tool in the MCP server.

Removes a tax ID from a customer. `taxIdId` is the tax ID's `id` on the customer: its canonical number, e.g.
`ATU12345678`. Past sales keep the check they were quoted with; future sales no longer use the ID. The type is
inferred again (spec §13.1): without a tax ID, a customer is a business only when declared one with a business
name. Emits `customer.updated`.

## At a glance

- **REST:** `DELETE /api/v1/customers/{id}/tax_ids/{taxIdId}`
- **MCP tool:** `customers_tax_ids_delete`
- **Operation ID:** `customers.tax_ids.delete`
- **Scope:** Brand
- **Permission:** `customers:write`
- **Risk tier:** `write`
- **Dry run:** Supported (send `Ownrecord-Dry-Run: true`)
- **Idempotency:** `Idempotency-Key` optional
- **Modes:** Test and live
- **Authentication:** API key with the `customers:write` scope
- **Since:** M4

## Request

### Path parameters

| Field     | Type       | Description                                                                  |
| --------- | ---------- | ---------------------------------------------------------------------------- |
| `id`      | `cus_…` ID | The customer's ID (`cus_…`).                                                 |
| `taxIdId` | string     | The tax ID's `id` on the customer: its canonical number, e.g. `ATU12345678`. |

### Body

This operation takes no body.

## Response

`200 OK` with a JSON object:

| Field                                      | Type                                                                  | Description                                                                                                                                                                                              |
| ------------------------------------------ | --------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `id`                                       | `cus_…` ID                                                            |                                                                                                                                                                                                          |
| `object`                                   | `"customer"`                                                          |                                                                                                                                                                                                          |
| `livemode`                                 | boolean                                                               |                                                                                                                                                                                                          |
| `entityId`                                 | `ent_…` ID                                                            |                                                                                                                                                                                                          |
| `brandId`                                  | `brd_…` ID                                                            |                                                                                                                                                                                                          |
| `email`                                    | string                                                                |                                                                                                                                                                                                          |
| `name`                                     | string or null                                                        |                                                                                                                                                                                                          |
| `businessName`                             | string or null                                                        |                                                                                                                                                                                                          |
| `locale`                                   | string or null                                                        |                                                                                                                                                                                                          |
| `type`                                     | one of `individual`, `business`, `unknown`                            | Inferred (spec §13.1): `business` with a tax ID that isn't rejected, or with a business name when declared a business. Tax is decided per sale: only a `valid` tax ID makes a sale business-to-business. |
| `declaredType`                             | one of `individual`, `business`, `unknown`                            | What you declared.                                                                                                                                                                                       |
| `billingAddress`                           | object or null                                                        |                                                                                                                                                                                                          |
| `taxIds`                                   | array of object                                                       |                                                                                                                                                                                                          |
| `taxIds[].id`                              | string                                                                | Identifies the tax ID on the customer: its canonical number, e.g. `ATU12345678`.                                                                                                                         |
| `taxIds[].type`                            | string                                                                | `eu_vat`, `gb_vat`, `ch_uid`/`ch_vat`, `no_org`/`no_vat`, `us_ein`, or another type (unverified).                                                                                                        |
| `taxIds[].value`                           | string                                                                | The number as given.                                                                                                                                                                                     |
| `taxIds[].country`                         | string                                                                |                                                                                                                                                                                                          |
| `taxIds[].number`                          | string or null                                                        | The canonical number (null for types Ownrecord can't check).                                                                                                                                             |
| `taxIds[].verification`                    | object                                                                | The latest check (spec §9.4).                                                                                                                                                                            |
| `taxIds[].verification.status`             | one of `valid`, `invalid`, `unavailable`, `format_only`, `unverified` | `valid`, `invalid`, `unavailable` (the register couldn't answer), `format_only` (no register: format and checksum) or `unverified` (a type Ownrecord can't check).                                       |
| `taxIds[].verification.source`             | string                                                                | Who decided: VIES, HMRC, CH_UID, FORMAT (format and checksum only) or NONE.                                                                                                                              |
| `taxIds[].verification.reason`             | string or null                                                        | Why, e.g. `not_registered` or `service_unavailable`.                                                                                                                                                     |
| `taxIds[].verification.checkedAt`          | date-time                                                             |                                                                                                                                                                                                          |
| `taxIds[].verification.consultationNumber` | string or null                                                        | The register's proof of the check (VIES request identifier, HMRC consultation number).                                                                                                                   |
| `taxIds[].verification.simulated`          | boolean                                                               | A fixture answer (development and test environments), not a register's.                                                                                                                                  |
| `taxIds[].history`                         | array of object                                                       | Earlier checks, newest first (at most 10).                                                                                                                                                               |
| `taxIds[].history[].status`                | one of `valid`, `invalid`, `unavailable`, `format_only`, `unverified` | `valid`, `invalid`, `unavailable` (the register couldn't answer), `format_only` (no register: format and checksum) or `unverified` (a type Ownrecord can't check).                                       |
| `taxIds[].history[].source`                | string                                                                | Who decided: VIES, HMRC, CH_UID, FORMAT (format and checksum only) or NONE.                                                                                                                              |
| `taxIds[].history[].reason`                | string or null                                                        | Why, e.g. `not_registered` or `service_unavailable`.                                                                                                                                                     |
| `taxIds[].history[].checkedAt`             | date-time                                                             |                                                                                                                                                                                                          |
| `taxIds[].history[].consultationNumber`    | string or null                                                        | The register's proof of the check (VIES request identifier, HMRC consultation number).                                                                                                                   |
| `taxIds[].history[].simulated`             | boolean                                                               | A fixture answer (development and test environments), not a register's.                                                                                                                                  |
| `taxIds[].addedAt`                         | date-time                                                             |                                                                                                                                                                                                          |
| `taxCountryLocked`                         | object or null                                                        | Where the customer's purchases are taxed (spec §9.3): set at the first successful payment, moved only when a top-up's evidence resolves to another country.                                              |
| `taxExempt`                                | object or null                                                        | Tax exemption (spec §9.5). Not applied yet: exemption certificates come in a later release.                                                                                                              |
| `processorRefs`                            | array of object                                                       | The customer at each payment processor used (set by checkout).                                                                                                                                           |
| `processorRefs[].processorConnectionId`    | `pcon_…` ID                                                           |                                                                                                                                                                                                          |
| `processorRefs[].customerRef`              | string                                                                |                                                                                                                                                                                                          |
| `risk`                                     | object                                                                |                                                                                                                                                                                                          |
| `risk.level`                               | one of `normal`, `elevated`, `blocked`                                |                                                                                                                                                                                                          |
| `risk.reasons`                             | array of string                                                       |                                                                                                                                                                                                          |
| `risk.firstPaymentAt`                      | date-time or null                                                     |                                                                                                                                                                                                          |
| `risk.totalPaid`                           | money                                                                 |                                                                                                                                                                                                          |
| `portalLastLoginAt`                        | date-time or null                                                     |                                                                                                                                                                                                          |
| `testClockId`                              | `clk_…` ID or null                                                    | Test mode: the test clock the customer was created on (spec §16.13).                                                                                                                                     |
| `metadata`                                 | object                                                                |                                                                                                                                                                                                          |
| `createdAt`                                | date-time                                                             |                                                                                                                                                                                                          |
| `updatedAt`                                | date-time                                                             |                                                                                                                                                                                                          |
| `deletedAt`                                | date-time or null                                                     | When the customer was deleted (soft delete); null while active.                                                                                                                                          |

## Examples

### Remove the Austrian VAT ID

The customer keeps its business name, so it stays a business.

```http
DELETE /api/v1/customers/cus_01m4ty3c2b5qx7mhd9k8w6s0aa/tax_ids/ATU00000000
Authorization: Bearer or_test_…
```

Response (`200`):

```json
{
  "id": "cus_01m4ty3c2b5qx7mhd9k8w6s0aa",
  "object": "customer",
  "livemode": false,
  "entityId": "ent_01m4tx5nj8emwbyf7y9vcf47x2",
  "brandId": "brd_01m4tx5nj8emwbyf7y9vcf47x4",
  "email": "billing@alpenapps.example",
  "name": "Lena Huber",
  "businessName": "Alpen Apps GmbH",
  "locale": "de-AT",
  "type": "business",
  "declaredType": "business",
  "billingAddress": {
    "line1": "Mariahilfer Straße 1",
    "line2": null,
    "city": "Wien",
    "postalCode": "1060",
    "region": null,
    "country": "AT"
  },
  "taxIds": [],
  "taxCountryLocked": null,
  "taxExempt": null,
  "processorRefs": [],
  "risk": {
    "level": "normal",
    "reasons": [],
    "firstPaymentAt": null,
    "totalPaid": {
      "amount": "0",
      "currency": "EUR"
    }
  },
  "portalLastLoginAt": null,
  "testClockId": null,
  "metadata": {
    "userId": "u_4821"
  },
  "createdAt": "2026-10-14T09:00:00.000Z",
  "updatedAt": "2026-10-14T09:30:00.000Z",
  "deletedAt": null
}
```

## Errors

| Code                                                                                         | HTTP status | When                                                                                             | What to do                                                                                                                                         |
| -------------------------------------------------------------------------------------------- | ----------- | ------------------------------------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------------------------------------- |
| [`validation_failed`](https://ownrecord.io/docs/reference/errors.md#validation_failed)       | 400         | `id` or `taxIdId` is malformed.                                                                  | Fix the fields listed in `details.issues` and send the request again.                                                                              |
| [`resource_not_found`](https://ownrecord.io/docs/reference/errors.md#resource_not_found)     | 404         | This brand has no such customer in this mode, or the customer has no tax ID with this `taxIdId`. | Check the ID and that your credentials are scoped to the right organization, entity, brand and mode.                                               |
| [`customer_deleted`](https://ownrecord.io/docs/reference/errors.md#customer_deleted)         | 400         | The customer was deleted.                                                                        | Create a new customer for this buyer. Deleted customers stay readable for the records they belong to, but can't be changed.                        |
| [`version_conflict`](https://ownrecord.io/docs/reference/errors.md#version_conflict)         | 409         | The customer changed at the same moment; retry.                                                  | Fetch the object again and retry the change.                                                                                                       |
| [`scope_required`](https://ownrecord.io/docs/reference/errors.md#scope_required)             | 400         | The request names no brand (an org or entity key without `Ownrecord-Brand`).                     | Call the operation with credentials or a target at its level: an organization, a legal entity, a brand or the platform (`details.required_scope`). |
| [`livemode_not_allowed`](https://ownrecord.io/docs/reference/errors.md#livemode_not_allowed) | 403         | You have no live-mode access, so you can't act on live customers.                                | Use test mode, or credentials for the target's mode. Developers need live access granted by an organization owner or admin.                        |
| [`permission_denied`](https://ownrecord.io/docs/reference/errors.md#permission_denied)       | 403         | You can't change this brand's customers (`customers:write`: owners, admins and support).         | Ask an organization owner or admin for a role or scope that allows this action.                                                                    |

It can also return these [common errors](https://ownrecord.io/docs/reference.md#common-errors): [`api_version_unsupported`](https://ownrecord.io/docs/reference/errors.md#api_version_unsupported), [`invalid_json`](https://ownrecord.io/docs/reference/errors.md#invalid_json), [`unsupported_media_type`](https://ownrecord.io/docs/reference/errors.md#unsupported_media_type), [`authentication_required`](https://ownrecord.io/docs/reference/errors.md#authentication_required), [`api_key_invalid`](https://ownrecord.io/docs/reference/errors.md#api_key_invalid), [`idempotency_key_reused`](https://ownrecord.io/docs/reference/errors.md#idempotency_key_reused), [`idempotency_in_progress`](https://ownrecord.io/docs/reference/errors.md#idempotency_in_progress), [`approval_required`](https://ownrecord.io/docs/reference/errors.md#approval_required), [`approval_rejected`](https://ownrecord.io/docs/reference/errors.md#approval_rejected), [`approval_expired`](https://ownrecord.io/docs/reference/errors.md#approval_expired), [`stale_approval`](https://ownrecord.io/docs/reference/errors.md#stale_approval), [`approval_policy_denied`](https://ownrecord.io/docs/reference/errors.md#approval_policy_denied), [`rate_limited`](https://ownrecord.io/docs/reference/errors.md#rate_limited), [`internal_error`](https://ownrecord.io/docs/reference/errors.md#internal_error).
