# Update a category

Updates an existing category. Accepted fields depend on the category type:

- Custom categories (custom: true): name and accounting_code_id are mutable; enabled returns 400.
- System categories (custom: false): enabled and accounting_code_id are mutable; name returns 400.

Endpoint: PATCH /v1/businesses/{client_id}/categories/{category_id}
Version: v1
Security: BearerAuth

## Path parameters:

  - `client_id` (integer, required)
    The ID of the business.
    Example: 123

  - `category_id` (string, required)
    The ID of the category.
    Example: "7cb19e45-1234-5678-abcd-ef9876543210"

## Request fields (application/json):

  - `name` (string)
    New display name. Only accepted for custom categories (custom: true). Returns 400 for system categories.
    Example: "Updated Category Name"

  - `enabled` (boolean)
    Whether this category is available for use. Only accepted for system categories (custom: false). Returns 400 for custom categories.

  - `accounting_code_id` (string,null)
    The ID of a GL code to map to this category. Pass null to remove an existing mapping. Must belong to the same business.
    Example: "3fa85f64-5717-4562-b3fc-2c963f66afa6"

## Response 200 fields (application/json):

  - `id` (string)
    The unique identifier for this category.
    Example: "7cb19e45-1234-5678-abcd-ef9876543210"

  - `name` (string)
    The display name of the category.
    Example: "Travel"

  - `custom` (boolean)
    Whether this is a custom category created by the business. System-defined categories have custom: false.

  - `enabled` (boolean)
    Whether this category is available for use on transactions.
    Example: true

  - `accounting_code_id` (string,null)
    The ID of the GL code mapped to this category, or null if no mapping exists.
    Example: "3fa85f64-5717-4562-b3fc-2c963f66afa6"

  - `created` (string)
    When this category was created in UTC.
    Example: "2025-01-01T00:00:00Z"

  - `updated` (string)
    When this category was last updated in UTC.
    Example: "2025-01-01T00:00:00Z"


## Response 400 fields

## Response 401 fields

## Response 403 fields

## Response 404 fields