An invoice number is a unique, sequential number assigned to each invoice. When used properly, invoice numbers make it easy to keep track of payments due.
Different people like to order their invoices in different ways, and accounting records typically reflect this fact.
There are just two rules to stick to regarding numbering invoices:
- Use sequential and chronological invoice numbers
- Make sure each invoice number is unique
How the numbers are structured is mostly up to you. We support 2 options:
- Global sequencing: For companies who don’t issue a lot of invoices, it’ll make sense to stick to a global sequencing format which means that invoice numbers wouldn’t change depending on the client, project, or goods sold.
- Numbers based on the document type: reflect the document type in the numbering system by starting the format with INV or INVOICE for invoices, PROFORMA for pro forma invoices, and so on.
To give you an idea of what various invoicing solutions propose, here are three examples of default invoice numbers used in QuickBooks, Xero, and FreeAgent.
FreeAgent – default number: INVOICE 001