Billing For merchants · Updated May 27, 2026

Creating and sending invoices

This guide shows you how to build an invoice, send it to a customer, get it paid, and fix the issues that come up most often.

How invoices work

An invoice bills a specific customer for one or more line items (your products and prices). You can create one by hand, and invoices are also generated automatically by subscriptions at each renewal. An invoice moves through a few states:

StatusMeaning
DraftBeing prepared — not yet issued. You can still edit everything.
OpenIssued and awaiting payment.
PaidPaid in full.
Past DueNot paid by the due date.
VoidCanceled — no longer owed.
UncollectibleWritten off as unlikely to be paid.
Partially Refunded / RefundedSome or all of the amount was returned.

Creating an invoice

  1. Start a new invoice and choose the customer (required).
  2. Add one or more line items — each is one of your product prices with a quantity. The currency is taken from the customer.
  3. Optionally add a memo, footer, or a custom invoice number.
  4. Confirm the invoice to issue it (this moves it from Draft to Open).

When you confirm, if the customer has a saved default payment method the invoice can be charged automatically; otherwise it is emailed to the customer to pay.

Sending an invoice and getting paid

Use Send invoice to email it (you can add extra recipients). The customer opens a hosted payment page and pays by card or another enabled method.

Note: an invoice for a zero amount won't be emailed — it needs a positive amount due and at least one valid recipient email.

Editing, voiding, and deleting

Common problems

1

"I can't edit my invoice"

Cause

Line items lock as soon as the invoice is issued (Open).

Solution

You can still edit the memo/footer. To change the amounts or items, void the invoice and create a new one — or duplicate it — and get it right while it's still a Draft.

2

The invoice is Past Due / unpaid

Cause

The customer didn't pay by the due date.

Solution

Re-send the invoice email or share the payment link. If the customer has a saved card, automatic charges retry a few times. If it truly won't be paid, mark it Uncollectible.

3

The customer never got the invoice email

Cause

The amount due is zero (sending is skipped), the email is invalid, or it was filtered to spam.

Solution

Confirm the invoice has a positive amount and a valid customer email, ask them to check spam, then re-send.

4

"Invoice number already exists"

Cause

The custom invoice number you entered is already in use, or doesn't match the allowed format (letters, numbers, and dashes).

Solution

Use a different number, or leave it blank to have one generated.

Error message reference

What you seeWhat it meansWhat to do
It isn't allowed to change status of this invoice.The status change isn't valid for this invoiceOnly Draft invoices can be edited/deleted; issued ones can be voided
Not has invoice itemsYou tried to issue an invoice with no line itemsAdd at least one line item before confirming
Invoice number already existsThat custom invoice number is takenUse a different number or auto-generate
Must contain at least one emailNo valid recipient to send toAdd a valid email address
No payment methods available for your location.No payment method is set up for the customer's countryEnable a payment method for that region

Still having trouble?

Contact Arca support and include: