Sequential, consistent invoice numbers keep your bookkeeping tidy and look professional to clients. This tool formats a prefix, the year and a zero-padded number into a clean invoice reference you can reuse.
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Frequently asked questions
How should I number invoices?
Use a consistent format like PREFIX-YEAR-0001 and increment sequentially — never reuse or skip numbers.
Does it have to be sequential?
Gaps and duplicates confuse accounting and can raise questions in an audit, so sequential is best.