# Update contact (/api-reference/contacts/updateContact)

`PATCH /contacts/{id}`

Base URL: `https://next-api.useplunk.com`

Update an existing contact's email, subscription state, or `data` fields.

## Path parameters

- `id`: string (required)

## Request body

- `email`: string (email) — Change the contact's email address. Returns 409 if another contact in the project already uses this email.
- `subscribed`: boolean — Update subscription state. Flipping this fires `contact.subscribed` or `contact.unsubscribed`.
- `data`: object — Patch contact data. `null` deletes a key, empty strings are ignored, primitives are stored. Reserved keys are silently filtered out.

Example:

```json
{
  "email": "user@example.com",
  "subscribed": false,
  "data": null
}
```

## Responses

### `200` — Contact updated

- `id`: string — Unique contact identifier
- `email`: string (email) — Contact email address
- `subscribed`: boolean — Subscription status
- `data`: object — Custom contact data fields
- `createdAt`: string (date-time)
- `updatedAt`: string (date-time)

```json
{
  "id": "string",
  "email": "user@example.com",
  "subscribed": false,
  "data": null,
  "createdAt": "2026-08-09T17:56:20.150Z",
  "updatedAt": "2026-08-09T17:56:20.150Z"
}
```

### `401` — Missing or invalid API key.

- `success`: enum (false)
- `error`: object
  - `code`: string — Machine-readable error code, e.g. `VALIDATION_ERROR`, `INVALID_API_KEY`, `IDEMPOTENCY_KEY_REUSED`.
  - `message`: string
  - `statusCode`: integer
  - `requestId`: string — Correlation ID for this request. Include it when contacting support.
  - `errors`: array<object> — Field-level detail, present on validation failures.
    items:
      - `field`: string — Dot-path of the offending field, e.g. `attachments.0.filename`.
      - `message`: string
      - `code`: string — Validation issue code, e.g. `invalid_type`, `too_big`, `reserved_event`.
      - `received`: object — The value that was received, when available.
  - `details`: object — Additional error context.
  - `suggestion`: string — Hint for fixing the request.
- `timestamp`: string (date-time)

```json
{
  "success": false,
  "error": {
    "code": "string",
    "message": "string",
    "statusCode": 0,
    "requestId": "string",
    "errors": [
      {
        "field": "string",
        "message": "string",
        "code": "string",
        "received": null
      }
    ],
    "details": null,
    "suggestion": "string"
  },
  "timestamp": "2026-08-09T17:56:20.150Z"
}
```

### `404` — The requested resource does not exist in this project.

- `success`: enum (false)
- `error`: object
  - `code`: string — Machine-readable error code, e.g. `VALIDATION_ERROR`, `INVALID_API_KEY`, `IDEMPOTENCY_KEY_REUSED`.
  - `message`: string
  - `statusCode`: integer
  - `requestId`: string — Correlation ID for this request. Include it when contacting support.
  - `errors`: array<object> — Field-level detail, present on validation failures.
    items:
      - `field`: string — Dot-path of the offending field, e.g. `attachments.0.filename`.
      - `message`: string
      - `code`: string — Validation issue code, e.g. `invalid_type`, `too_big`, `reserved_event`.
      - `received`: object — The value that was received, when available.
  - `details`: object — Additional error context.
  - `suggestion`: string — Hint for fixing the request.
- `timestamp`: string (date-time)

```json
{
  "success": false,
  "error": {
    "code": "string",
    "message": "string",
    "statusCode": 0,
    "requestId": "string",
    "errors": [
      {
        "field": "string",
        "message": "string",
        "code": "string",
        "received": null
      }
    ],
    "details": null,
    "suggestion": "string"
  },
  "timestamp": "2026-08-09T17:56:20.150Z"
}
```

### `409` — An existing contact already uses the email you're trying to set.

- `success`: enum (false)
- `error`: object
  - `code`: string — Machine-readable error code, e.g. `VALIDATION_ERROR`, `INVALID_API_KEY`, `IDEMPOTENCY_KEY_REUSED`.
  - `message`: string
  - `statusCode`: integer
  - `requestId`: string — Correlation ID for this request. Include it when contacting support.
  - `errors`: array<object> — Field-level detail, present on validation failures.
    items:
      - `field`: string — Dot-path of the offending field, e.g. `attachments.0.filename`.
      - `message`: string
      - `code`: string — Validation issue code, e.g. `invalid_type`, `too_big`, `reserved_event`.
      - `received`: object — The value that was received, when available.
  - `details`: object — Additional error context.
  - `suggestion`: string — Hint for fixing the request.
- `timestamp`: string (date-time)

```json
{
  "success": false,
  "error": {
    "code": "string",
    "message": "string",
    "statusCode": 0,
    "requestId": "string",
    "errors": [
      {
        "field": "string",
        "message": "string",
        "code": "string",
        "received": null
      }
    ],
    "details": null,
    "suggestion": "string"
  },
  "timestamp": "2026-08-09T17:56:20.150Z"
}
```

## Example request

```bash
curl -X PATCH 'https://next-api.useplunk.com/contacts/{id}' \
  -H 'Authorization: Bearer YOUR_API_KEY' \
  -H 'Content-Type: application/json' \
  -d '{"email":"user@example.com","subscribed":false,"data":null}'
```