> For the complete documentation index, see [llms.txt](https://chekin.gitbook.io/chekin-public-api/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://chekin.gitbook.io/chekin-public-api/api-reference/einvoicing/invoices.md).

# Invoices

Invoices are the documents issued to the guest and registered with the tax authority. Applies to the **MyData**, **AT** and **AdE** providers — for **AADE**, use [Short-Term Declarations](/chekin-public-api/api-reference/einvoicing/short-term-declarations.md) instead.

{% hint style="warning" %}
The issuing process is **asynchronous**: the invoice is initially created with status `NEW`/`PENDING` and then processed in the background. The PDF (`file_url`) only becomes available once the status is `COMPLETED`.
{% endhint %}

### Suggested workflow

1. Make sure at least one **registered guest** exists in the reservation.
2. [Create the invoicing items](/chekin-public-api/api-reference/einvoicing/invoicing-items.md) of the reservation. You can [retrieve the sub-totals](/chekin-public-api/api-reference/einvoicing/invoices/retrieve-sub-totals.md) to check the amounts grouped per category.
3. Provide the `supplier_id`, the `reservation_id` and the `series_id` of the required invoice type.
4. Send the [Issue an Invoice](/chekin-public-api/api-reference/einvoicing/invoices/issue-an-invoice.md) request and store the returned invoice IDs.
5. Monitor the status by polling [List Invoices](/chekin-public-api/api-reference/einvoicing/invoices/list-invoices.md) or by listening to the supplier webhooks.
6. Once the status is `COMPLETED`, download the PDF from `file_url`.
7. If the invoice has to be cancelled or adjusted, [issue a credit note](/chekin-public-api/api-reference/einvoicing/invoices/issue-a-credit-note.md).

### How many invoices are created

| Provider           | Result                                                                                    |
| ------------------ | ----------------------------------------------------------------------------------------- |
| MyData (`MY_DATA`) | **Multiple** — one invoice per non-zero category (`standard`, `fee`, `accommodation_tax`) |
| AT (`AT`)          | **Multiple** — one invoice per non-zero category (`standard`, `fee`)                      |
| AdE (`ADE`)        | **Single** — one invoice combining all applicable item categories                         |

### Invoice Statuses (all providers)

| Status                     | Description                                     |
| -------------------------- | ----------------------------------------------- |
| `NEW`                      | Invoice created, waiting for processing         |
| `PENDING`                  | Processing in progress                          |
| `GENERATED`                | Invoice has been generated                      |
| `READY_FOR_PDF_EXTRACTION` | Ready for PDF extraction                        |
| `COMPLETED`                | Successfully completed; `file_url` is available |
| `ERROR`                    | Error during creation                           |
| `CANCELLATION_IN_PROGRESS` | Credit note / cancellation in progress          |
| `CANCELLED`                | Successfully cancelled                          |
| `CANCELLATION_ERROR`       | Error during cancellation                       |