> For the complete documentation index, see [llms.txt](https://support.ordereazi.com/central/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.ordereazi.com/central/order-management/documents/sales-documents/tax-invoices.md).

# Tax invoices

An invoice for the wrong quantity, or for something you've already invoiced, means a credit note, a correction in your books, and an unhappy client. A tax invoice in OrderEazi is created from the sales order, for all or part of the order. OrderEazi checks what's still outstanding before it creates the invoice, and the invoice syncs to your accounting system.

### Before you start

You'll need the **Create Documents** permission, in the **Projects** permission group. The project needs a sales order, and every line must be linked to a product. If your organisation uses an accounting system, the client must be synced to it.

### How to create a tax invoice

> **Warning:** A tax invoice is sent to your accounting system once it's created, and it can't be voided. To reverse it later, you'll need a credit note. Check the quantities and dates before step 6.

1. At the bottom of the project, select **Create Documents**.
2. Next to **Tax Invoice(s)**, select **Create**.
3. Enter the **Invoice Date** and check the **Due Date**.
4. For each line, enter the quantity to invoice in **Allocate**.
5. Check the email to your client.
6. Select **Create and Email**, or **Create** if email is turned off.

You see "Tax Invoice Created" and "Please check Email Delivery Status in Outbox". The project's history shows "Tax Invoice Created" with its number. If your organisation uses an accounting system, the invoice email is held in your outbox while the invoice syncs.

If the project's lines come from more than one warehouse or sales order, the screen shows a group for each, with its own **Create** button.

### How tax invoices work

* **The due date:** It starts from the client's payment terms. If the client has none, it's 30 days after the invoice date. A due date before the invoice date is moved to the day after the invoice date.
* **Partial invoicing:** You can invoice part of the order now and the rest later. The **Tax Invoice(s)** row shows **Partially Created** until every line is invoiced, then **Completed**.
* **No double invoicing:** When you select **Create**, OrderEazi checks each line against what's already been invoiced on the project.
* **Accounting sync:** Tax invoices sync to your connected accounting system. **Awaiting sync** shows on the row until they do.

**Example:** You've delivered 15 of 20 chairs, so you invoice 15. The row shows **Partially Created**. A week later, a colleague tries to invoice 20 from an old screen. OrderEazi refuses with "Cannot create this invoice - CHAIR-01 (requested 20, only 5 outstanding - already invoiced on" and your invoice number, and they invoice the last 5 instead.

### When a tax invoice can't be created

* **"You first have to create a Sales Order before you can generate a tax invoice.":** Create the sales order first.
* **"Cannot create invoice - insufficient available stock for:":** Your organisation blocks invoices for stock you don't have, and the listed products are short.
* **"Tax Invoice already created in full":** Every line has already been invoiced.
* **"Please allocate at least one unit to the Invoice":** Enter a quantity on at least one line.

### Related pages

* [Credit notes](/central/order-management/documents/credits-returns-and-voids/credit-notes.md): reverse all or part of a tax invoice
* [Sales orders](/central/order-management/documents/sales-documents/sales-orders.md): the document a tax invoice comes from
* [Payments](/central/order-management/projects/payments.md): send a payment link for the invoice