Why the distinction matters in practice
Most of the time nobody minds if you use the words loosely. It starts mattering in three situations, and in all three the cost of getting it wrong lands on you rather than your client.
When you are chasing payment. A receipt is not evidence that a debt exists — it is evidence that one was discharged. If you need to pursue an unpaid amount, the invoice is the document that establishes what was owed, when it fell due and on what terms. Sending something headed “receipt” for money you have not received undermines the claim you may later need to make.
When you are VAT registered. In the UK, the tax point is generally the invoice date, not the date the money arrives. Your customer reclaims input VAT against a valid VAT invoice, and a receipt alone will not support that reclaim. This is the most common reason an accounts payable team sends a document back.
When you are audited. Both documents together show the full transaction: what was agreed, what was charged, and what was paid. A receipt on its own leaves the question of what the payment was for, which is exactly the question an inspection is asking.
What each document must carry
An invoice needs a unique sequential number, the issue date, a payment due date, both parties’ names and addresses, a description of what was supplied, the amount due, and the payment terms. If you are VAT registered it also needs your VAT number, the rate applied and the VAT amount shown separately.
A receipt needs the date payment was received, the amount received, what it was for, the payment method, and — critically — a reference to the invoice it settles. That last one is the field most often left off, and it is the one that makes reconciliation possible months later.
Numbering them
Keep two sequences. Invoices run INV-0001 upward; receipts run their own series. Sharing one sequence creates gaps in your invoice numbering that you will have to explain, and makes it far harder to demonstrate which document supported which VAT return.
Partial payments
A deposit produces a receipt for the amount received while the invoice remains partly outstanding. Do not issue a receipt for the full invoice value until the full amount has arrived — an overstated receipt is very difficult to walk back if the balance is never paid.
Last reviewed August 2026.