---
title: "Define or change a custom contact field"
method: PUT
path: "/contact-fields/{key}"
tags: ["Campaigns"]
---

# Define or change a custom contact field

`PUT /contact-fields/{key}`

## Request

- Base URL: `https://sendhq.cc/api/v1`
- URL: `https://sendhq.cc/api/v1/contact-fields/{key}`
- Auth: HTTP bearer
- TypeScript: <https://skmtc.dev/sendhq/apis/sendhq-api/docs/contact-fields/:key/put.ts> (a function with typed inputs; its response is checked against the schema)

Create or update the field `key` (a lowercase letter, then up to 39 of a-z, 0-9, and `_`). `type` is `text` (default), `number`, or `date`. Built-in merge tags (`email`, `name`, `first_name`, `last_name`, `fields`, `unsubscribe_url`) cannot be used. A workspace may define 50 fields.

## Path parameters

- `key` string, required

## Request body

- object
  - `label` string, required
  - `type` string, required

## Response `200`

Successful response

- object
  - `key` string, required
  - `label` string, required
  - `type` string, required
  - `createdAt` string, date-time, required

## Other responses

- `400`: Invalid request
- `401`: Missing or invalid authentication
- `402`: A paid entitlement is required for this recipient or feature
- `403`: The workspace, domain, policy, or suppression state forbids the operation
- `404`: Tenant-scoped resource not found
- `409`: Resource state or idempotency conflict
- `413`: Attachment count or bytes exceed the accepted limit
- `422`: Request validation or suppression check failed
- `423`: Sending is paused for this sender identity or workspace; the message gives the reason and how to appeal
- `429`: A monthly, daily, or trial usage limit was reached
- `500`: Unexpected server error
- `502`: An upstream provider operation failed
- `503`: A required provider or signing configuration is unavailable
- `default`: An error response using SendHQ's standard JSON envelope

---

[API](https://skmtc.dev/sendhq/apis/sendhq-api.md) - [All operations](https://skmtc.dev/sendhq/apis/sendhq-api/llms.txt) - [OpenAPI document](https://skmtc.dev/sendhq/apis/sendhq-api/revisions/98e39e48cb9a?raw)