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

# Invoices

> Create, read, amend, cancel, reactivate and delete invoices, and reach their lines, notes, files, fulfillments and returns.

An invoice bills an account for items, either on its own or raised from an order. This area has 30 endpoints: create, read, update, amend, cancel, reactivate and delete invoices; raise an invoice for an order; read their lines, KPIs and PDF links; add, read and delete notes and note files; and read their fulfillments, return merchandise authorisations and custom objects. Every SDK supports all of them.

## At a glance

| Endpoint | Method | Path | What it does |
| - | - | - | - |
| [List invoices](https://exsited.mintlify.site/api-reference/invoices/list-invoices.md) | GET | `/invoices` | Returns one page of invoices, with a cursor for the next page. |
| [Retrieve an invoice](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoice.md) | GET | `/invoices/{invoice_id}` | Returns one invoice by its `id`, including its lines. |
| [Retrieve an invoice's information](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoices-information.md) | GET | `/invoices/{invoice_id}/information` | Returns an invoice's core information, without its lines. |
| [Retrieve an invoice's PDF links](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoices-pdf-links.md) | GET | `/invoices/{invoice_id}/pdf` | Returns links to the invoice's PDF, not the PDF file itself. |
| [Create an invoice](https://exsited.mintlify.site/api-reference/invoices/create-an-invoice.md) | POST | `/invoices` | Creates an invoice for an account and returns it. |
| [Update an invoice's information](https://exsited.mintlify.site/api-reference/invoices/update-an-invoices-information.md) | PATCH | `/invoices/{invoice_id}/information` | Changes an invoice's note or customer purchase order number and returns the invoice. |
| [Amend an invoice](https://exsited.mintlify.site/api-reference/invoices/amend-an-invoice.md) | POST | `/invoices/{invoice_id}/amend` | Adds, changes or removes invoice lines and returns the invoice. |
| [Cancel an invoice](https://exsited.mintlify.site/api-reference/invoices/cancel-an-invoice.md) | POST | `/invoices/{invoice_id}/cancel` | Cancels an invoice and returns it with `status` `inactive`. |
| [Reactivate an invoice](https://exsited.mintlify.site/api-reference/invoices/reactivate-an-invoice.md) | POST | `/invoices/{invoice_id}/reactivate` | Reactivates a cancelled invoice and returns it with `status` `active`. |
| [Delete an invoice](https://exsited.mintlify.site/api-reference/invoices/delete-an-invoice.md) | DELETE | `/invoices/{invoice_id}` | Deletes an invoice. |
| [List an invoice's item fulfillments](https://exsited.mintlify.site/api-reference/invoices/list-an-invoices-item-fulfillments.md) | GET | `/invoices/{invoice_id}/item_fulfillments` | Returns one page of the item fulfillments recorded against an invoice. |
| [Retrieve an invoice's item fulfillment](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoices-item-fulfillment.md) | GET | `/invoices/{invoice_id}/item_fulfillments/{fulfillment_id}` | Returns one item fulfillment recorded against an invoice. |
| [List an invoice's return merchandise authorisations](https://exsited.mintlify.site/api-reference/invoices/list-an-invoices-return-merchandise-authorisations.md) | GET | `/invoices/{invoice_id}/return_merchandise_authorisations` | Returns one page of the return merchandise authorisations raised against an invoice. |
| [Retrieve an invoice's return merchandise authorisation](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoices-return-merchandise-authorisation.md) | GET | `/invoices/{invoice_id}/return_merchandise_authorisations/{rma_id}` | Returns one return merchandise authorisation raised against an invoice. |
| [List an invoice's notes](https://exsited.mintlify.site/api-reference/invoices/list-an-invoices-notes.md) | GET | `/invoices/{invoice_id}/notes` | Returns one page of the notes on an invoice. |
| [Retrieve an invoice note](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoice-note.md) | GET | `/invoices/{invoice_id}/notes/{note_id}` | Returns one note on an invoice. |
| [Create an invoice note](https://exsited.mintlify.site/api-reference/invoices/create-an-invoice-note.md) | POST | `/invoices/{invoice_id}/notes` | Adds a note, and optionally a file, to an invoice and returns the note. |
| [Delete an invoice note](https://exsited.mintlify.site/api-reference/invoices/delete-an-invoice-note.md) | DELETE | `/invoices/{invoice_id}/notes/{note_id}` | Deletes a note from an invoice. |
| [List an invoice note's files](https://exsited.mintlify.site/api-reference/invoices/list-an-invoice-notes-files.md) | GET | `/invoices/{invoice_id}/notes/{note_id}/files` | Returns the files attached to a note on an invoice. |
| [Retrieve an invoice note file](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoice-note-file.md) | GET | `/invoices/{invoice_id}/notes/{note_id}/files/{file_id}` | Returns the details of one file attached to a note, not the file's contents. |
| [List an order's invoices](https://exsited.mintlify.site/api-reference/invoices/list-an-orders-invoices.md) | GET | `/orders/{order_id}/invoices` | Returns one page of the invoices raised for an order. |
| [Create an invoice for an order](https://exsited.mintlify.site/api-reference/invoices/create-an-invoice-for-an-order.md) | POST | `/orders/{order_id}/invoices` | Raises an invoice against an order and returns it. |
| [Retrieve an invoice's KPIs](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoices-kpis.md) | GET | `/invoices/{invoice_id}/kpis` | Returns an invoice's key figures, such as payment applied and amount outstanding. |
| [List an invoice's lines](https://exsited.mintlify.site/api-reference/invoices/list-an-invoices-lines.md) | GET | `/invoices/{invoice_id}/lines` | Returns all the lines of an invoice. |
| [Retrieve an invoice line](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoice-line.md) | GET | `/invoices/{invoice_id}/lines/{line_id}` | Returns one line of an invoice. |
| [Retrieve a credit note application through an invoice](https://exsited.mintlify.site/api-reference/invoices/retrieve-a-credit-note-application-through-an-invoice.md) | GET | `/invoices/{invoice_id}/credit_note_applications/{credit_note_application_id}` | Returns one credit note application by its `id`. |
| [List an invoice's custom objects](https://exsited.mintlify.site/api-reference/invoices/list-an-invoices-custom-objects.md) | GET | `/invoices/{invoice_id}/custom_objects` | Returns one page of the custom objects defined for invoices. |
| [Retrieve an invoice's custom object](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoices-custom-object.md) | GET | `/invoices/{invoice_id}/custom_objects/{custom_object_id}` | Returns one custom object with this invoice's instances of it. |
| [Retrieve an invoice's custom object instance](https://exsited.mintlify.site/api-reference/invoices/retrieve-an-invoices-custom-object-instance.md) | GET | `/invoices/{invoice_id}/custom_objects/{custom_object_id}/instances/{instance_id}` | Returns one instance of a custom object on an invoice. |
| [Delete an invoice note file](https://exsited.mintlify.site/api-reference/invoices/delete-an-invoice-note-file.md) | DELETE | `/invoices/{invoice_id}/notes/{note_id}/files/{file_id}` | Deletes one file from a note on an invoice. |

## Before you call

Register your API credentials once when your app starts, as shown in
[Authentication](https://exsited.mintlify.site/authentication.md). Every SDK sample on these pages then gets its client in one line.
With cURL, send the access token in an `Authorization` header: `Authorization: Bearer $ACCESS_TOKEN`.

## Things to know

* **Pass an invoice's `id`, never its `uuid`.** Every `{invoice_id}` is the invoice's `id`, such as `INV-0001`.
* **Write bodies go under an `invoice` key.** Create, update, amend, cancel and reactivate all wrap their fields in `invoice`. Amend, cancel, reactivate and creating an invoice for an order also work with no body.
* **Money comes back as text.** Amounts such as `total`, `subtotal` and `due` are strings like `"12.00"`. `discount_amount` and a line's tax `rate` are numbers.
* **The invoice listing pages by cursor.** Records are under `data`. Pass `pagination.next_cursor` back as `cursor` while `pagination.has_more` is `true`.
* **Only a single read carries the lines.** A listing entry has no `lines`; retrieve the invoice, or list its lines, to see them.
* **Some reads under an invoice do not check the invoice.** The credit note application read returns any application under any invoice that exists.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.