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Custom Invoice Numbering

In Clerk Invoices, you can use custom invoice numbers with a mix of letters and digits. When you open a new invoice form, Clerk will take the number of last created invoice and increment the numeric part of it.

For example, if the last created invoice has the number INV-385, the create invoice form will put INV-386 in the invoice number field. And you have the freedom to change it as you want. Or continue the automatic numbering and leave the number as is.

To give you the numbering freedom, Clerk does not control the uniqueness of the invoice number when you save the invoice. So, if you open 2 new invoice forms in separate browser tabs, Clerk will suggest the same next “unique” invoice number to both forms, since both forms rely on the same last created invoice.