Chapter 10
When do I need an invoice, and when is a receipt enough?
For most counter sales, a receipt is the whole answer — the same sale becomes an invoice the moment the buyer needs their own name and details on the paper, not because you did anything differently in the sale itself.
Every sale is recorded the same way underneath, whatever you end up printing. A receipt is what a walk-in customer needs: proof of what they bought and what they paid. An invoice is the same record with the buyer's own details attached, which matters when THEY need to show the purchase in their own books — a business customer buying for their shop, not a person buying for themselves.
What decides it, and what you do not have to decide
You do not choose invoice-or-receipt as a separate step at the till — you decide it by whether you attach a customer to the sale. Attach one, and their details print. Leave it a walk-in sale, and it does not.
What can wait: getting a customer's exact registered details on file before their first purchase is not required to sell to them today. A sale can be corrected to name a customer afterwards, and the paper reprinted, once you have what you need.