---
title: "Update a property"
method: PATCH
path: "/audience/properties/{propertyId}"
tags: ["Audience"]
---

# Update a property

`PATCH /audience/properties/{propertyId}`

## Request

- Base URL: `https://app.lettr.com/api`
- URL: `https://app.lettr.com/api/audience/properties/{propertyId}`
- Auth: HTTP bearer

Update the property's fallback value. The `name` and `type` fields cannot be changed (they would orphan data on existing contacts). If the request body contains no recognized fields, the property is returned unchanged with a `200` response. Requires the `audience:write` scope and is blocked for sandbox API keys.

## Path parameters

- `propertyId` string, uuid, required

## Request body

- UpdateAudiencePropertyRequest: Update a property's fallback value. The `name` and `type` fields are immutable (changing them would orphan data on existing contacts) and must not be provided.
  - `fallback_value` string, nullable

## Response `200`

Updated

- ShowAudiencePropertyResponse
  - `message` string, required
  - `data` AudiencePropertyView, required
    - `id` string, uuid, required
    - `name` string, required
    - `type` 'string' | 'number' | 'boolean' | 'date' | 'json', required: Data type of the property
    - `fallback_value` string, nullable, required
    - `purpose` 'communication_language' | 'null', nullable: Role the property is designated for. `communication_language` marks the property campaigns read the recipient language from; only one property per team can hold it.
    - `created_at` string, date-time, required

## Other responses

- `401`: Unauthorized - Missing or invalid API key
- `403`: Forbidden - API key does not have the required scope
- `404`: Resource not found
- `422`: Validation error
- `500`: Internal server error
- `503`: Service unavailable - the API key could not be verified, so the request was not processed. This does not mean the key is invalid; retry after the delay given in the Retry-After header.

---

[API](https://skmtc.dev/lettr/apis/lettr-api.md) · [All operations](https://skmtc.dev/lettr/apis/lettr-api/llms.txt) · [OpenAPI document](https://skmtc.dev/lettr/apis/lettr-api/revisions/48ef0dac1ebd?raw)