What is an invoice?
An invoice is a bill you send a customer after you've delivered work or goods. It states what was provided, how much is owed, and when payment is due. Once sent, an invoice is a formal payment request — and the start of your accounts receivable.
In practice
A freelance designer finishes a logo project and sends invoice INV-2026-014: 1 x Logo design at $800, 3 x Revision rounds at $75, subtotal $1,025, plus 8% sales tax ($82), total due $1,107, payable net 30. The number, dates, and line items give both sides an exact record if there's ever a dispute.
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Create an invoice — freeFrequently asked questions
What's the difference between an invoice and a receipt?
An invoice requests payment; a receipt confirms payment was received. You send the invoice first, and the receipt after the customer pays.
When should I send an invoice?
As soon as the work is delivered or the goods ship. Same-day invoicing gets you paid faster — every week of delay adds days to your collection time.
Does an invoice have to include tax?
It depends on your jurisdiction and what you sell. If you're registered to collect sales tax or VAT, show it as its own line; if not, don't invent it. Check your local rules.