# Invoices

Create invoices, invoice receipts, simplified invoices, vat moss invoices, credit notes & debit notes and send them to your clients.

## List All

 - [GET /invoices.json](https://docs.invoicexpress.com/invoices/listinvoices.md): Returns a list of invoices.

## Create Invoice

 - [POST /{invoices-type}.json](https://docs.invoicexpress.com/invoices/createinvoice.md): Creates a new invoice, simplified_invoice, invoice_receipt, credit_note or debit_note.



### Creating new clients or items along with the documents
This method also allows to create a new client and/or new items in the same request with the following behavior:
* If the client name does not exist, a new one is created.
* If items do not exist with the given names, new ones will be created.
* If item name already exists, the item is updated with the new values.

### Taxes
Regarding item taxes, if the tax name is not found, the default tax is applyed to that item. Portuguese accounts should also send the IVA exemption reason if the invoice contains exempt items (IVA 0%).

> Note: Simplified Invoices are only available in Portugal.

## Get Invoice

 - [GET /{invoices-type}/{document-id}.json](https://docs.invoicexpress.com/invoices/getinvoice.md)

## Update Invoice

 - [PUT /{invoices-type}/{document-id}.json](https://docs.invoicexpress.com/invoices/updateinvoice.md): Updates a new invoice, simplified_invoice, invoice_receipt, credit_note or debit_note.



### Creating new clients or items along with the invoice
This method also allows to create a new client and/or new items in the same request with the following behavior:
* If the client name does not exist, a new one is created.
* If items do not exist with the given names, new ones will be created.
* If item name already exists, the item is updated with the new values.

### Taxes
Regarding item taxes, if the tax name is not found, the default tax is applyed to that item. Portuguese accounts should also send the IVA exemption reason if the invoice contains exempt items (IVA 0%).

> Note: Simplified Invoices are only available in Portugal.

## Change Invoice State

 - [PUT /{invoices-type}/{document-id}/change-state.json](https://docs.invoicexpress.com/invoices/changeinvoicestate.md): Changes the state of invoice documents.

| From | To | State on Request Body | Notes |
| :--- | :--- | :--- | :--- |
| draft | final | finalized | All documents. |
| draft | settled | finalized | Only invoice_receipt. |
| draft | deleted | deleted | All documents. |
| final | canceled | canceled | All documents. |
| settled | canceled | canceled | Only invoice_receipt. |
| final | settled | settled | All documents. |
| settled | final | unsettled | Only credit_note and debit_note. |

## Send Invoice by Email

 - [PUT /{invoices-type}/{document-id}/email-document.json](https://docs.invoicexpress.com/invoices/sendinvoiceemail.md)

## Generate PDF

 - [GET /api/pdf/{document-id}.json](https://docs.invoicexpress.com/invoices/generatepdf.md)

## Get QR Code

 - [GET /api/qr_codes/{document-id}.json](https://docs.invoicexpress.com/invoices/getqrcode.md)

## Related Documents

 - [GET /document/{document-id}/related_documents.json](https://docs.invoicexpress.com/invoices/relateddocs.md)

## Generate Payment

 - [POST /documents/{document-id}/partial_payments.json](https://docs.invoicexpress.com/invoices/generatepayment.md)

## Cancel Payment

 - [PUT /receipts/{receipt-id}/change-state.json](https://docs.invoicexpress.com/invoices/cancelreceipt.md)

## Generate PDF

 - [GET /api/pdf/{document-id}.json](https://docs.invoicexpress.com/estimates/generatepdf.md)

## Generate PDF

 - [GET /api/pdf/{document-id}.json](https://docs.invoicexpress.com/guides/generatepdf.md)

## Get QR Code

 - [GET /api/qr_codes/{document-id}.json](https://docs.invoicexpress.com/guides/getqrcode.md)