tools

Invoice number generator

Generate unique, sequential invoice numbers with optional prefixes and year segments.

Every invoice needs a unique number. This guide and InvoyFlow auto-numbering help you avoid duplicates and gaps that confuse clients and accountants.

InvoyFlow assigns sequential numbers automatically — separate sequences for invoices, estimates, and credit notes.

How it works

Use INV-, EST-, or client codes in your numbering scheme.

Reset or include the year (2026-0042) for easier filing.

InvoyFlow tracks the last number so you never reuse one.

Voided invoices keep their number with a clear status.

Yes. Set a prefix and starting number in InvoyFlow settings.

The number stays assigned — void status prevents reuse while keeping audit trails clean.

Create a polished invoice in under two minutes — no accounting degree required.

Accept card and PayPal payments on every invoice with one-click setup.

Win work with estimates, then convert to invoices and issue receipts automatically.

Start free. Core is $8/mo, Unlimited is $15/mo — no surprise fees.