> 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/send-an-invoice-to-a-customer.md).

# Send an invoice to a customer

When an invoice is ready, use the Send button in the action bar at the top of the invoice. Save your changes first, because the Send button stays disabled while there are unsaved edits, and the invoice needs at least one line item and a recipient (an existing contact or a valid email address).

When you send, Essential emails the invoice to the customer, includes a PDF copy, and moves the invoice from Draft to Unpaid (or Overdue if the due date has already passed, or Paid if the total is zero). Follow-up and resend emails also include the current PDF. After it's sent the contents are locked, and you can Resend it from the ... menu.

Before sending, review the Email Reply To and custom message. Reply To defaults to your login email. If your business has turned off **Reply to sender** under Settings -> Invoicing, the field is hidden and replies go to the business email instead.

If the customer has autopay turned on, the Send button is replaced by Charge Payment Method, which charges their saved payment method instead of emailing for payment.

> **Where to find it:** On the open invoice, the Send button in the action bar at the top

## Related guides

* [Customize your invoice email and receipt templates](/administration/settings/customize-your-invoice-email-and-receipt-templates.md)
* [Receipts, Finalize Without Sending, and Resend](/revenue/invoices/receipts-finalize-without-sending-and-resend.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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