> ## Documentation Index
> Fetch the complete documentation index at: https://docs.antei.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Update Invoice

> Update specific fields of an existing invoice.

This endpoint allows partial updates to an invoice. Common fields that can be updated:

* `status` (e.g., to mark as paid or void)
* `metadata` or internal tags
* `due_date`

> ⚠️ You cannot update financial fields like line items or tax amounts after creation. For corrections, use credit notes or cancel-and-recreate strategy.


## OpenAPI

````yaml PATCH /invoices/{id}
openapi: 3.0.1
info:
  title: Antei API Reference
  description: >-
    Programmatic access to Antei’s platform. Use this API to manage core objects
    and retrieve taxation insights.
  version: 1.0.0
  license:
    name: MIT
  contact:
    name: Antei Developer Support
    email: support@antei.com
    url: https://antei.com
servers:
  - url: https://api.antei.com
security:
  - bearerAuth: []
paths:
  /invoices/{id}:
    patch:
      summary: Update invoice metadata or status
      description: >-
        Update editable fields such as metadata, notes, or status. Line items
        cannot be edited after invoice is sent.
      parameters:
        - name: id
          in: path
          required: true
          schema:
            type: string
      requestBody:
        required: true
        content:
          application/json:
            schema:
              $ref: '#/components/schemas/UpdateInvoice'
      responses:
        '200':
          description: Invoice updated
          content:
            application/json:
              schema:
                $ref: '#/components/schemas/Invoice'
components:
  schemas:
    UpdateInvoice:
      type: object
      properties:
        metadata:
          type: object
          additionalProperties:
            type: string
        internal_notes:
          type: string
        status:
          type: string
          enum:
            - draft
            - sent
            - paid
            - void
    Invoice:
      type: object
      properties:
        id:
          type: string
        invoice_number:
          type: string
        status:
          type: string
          enum:
            - draft
            - sent
            - paid
            - void
        contact_id:
          type: string
        transaction_ids:
          type: array
          items:
            type: string
        currency:
          type: string
        amount:
          type: number
          format: float
        issue_date:
          type: string
          format: date
        due_date:
          type: string
          format: date
        metadata:
          type: object
          additionalProperties:
            type: string
      required:
        - invoice_number
        - contact_id
        - status
        - currency
        - amount
  securitySchemes:
    bearerAuth:
      type: http
      scheme: bearer

````