> For the complete documentation index, see [llms.txt](https://learn.withessential.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://learn.withessential.com/revenue/invoices/why-cant-i-save-an-invoice.md).

# Why can't I save an invoice?

If the Save button stays disabled, the invoice is missing something it requires. An invoice saves only once it has a customer and property, at least one line item, payment terms selected, and at least one unsaved change.

Unlike a quote, an invoice doesn't need terms and conditions and its total can be zero. The most common cause of a greyed-out Save is payment terms not being set, so check the Payment Terms field below the Invoice date.

> **Where to find it:** On the open invoice, check the Save button, the line items, and the Payment Terms field

## Related guides

* [Why can't I edit an invoice?](/revenue/invoices/why-cant-i-edit-an-invoice.md)
* [Why can't I send an invoice?](/revenue/invoices/why-cant-i-send-an-invoice.md)
* [Add a line item to an invoice](/revenue/invoices/add-a-line-item-to-an-invoice.md)
* [Apply a discount to an invoice](/revenue/invoices/apply-a-discount-to-an-invoice.md)
* [Attach files or reports to an invoice](/revenue/invoices/attach-files-or-reports-to-an-invoice.md)


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