A receipt and an invoice are documents on opposite sides of a payment. The invoice requests money and comes first. The receipt confirms money was received and comes afterwards. In a payables process the distinction is consequential rather than academic, because entering the wrong one creates either a duplicate payment or a missing obligation.
The invoice, before
Issued by the supplier, stating what was supplied, what is owed and by when, with a unique number and terms. It creates an obligation in your records and starts the payment clock. In business it is a claim to be verified rather than a bill to be settled, which is why it is checked against what was ordered and what arrived.
The receipt, after
Issued after payment, confirming a specific amount was received against a specific obligation. It evidences settlement. In business payables the remittance advice does much of the same work from the payer's side, listing which invoices a transfer covered so the supplier can allocate it without telephoning to ask.
What goes wrong when they are confused
An expense receipt entered as a payable creates an obligation for something already paid, usually on a card, and it will eventually be paid again. An invoice treated as evidence of payment leaves an obligation open that somebody thinks is closed. Both are systematic errors when the capture process does not classify document types.
Which is why classification comes first
Before extracting fields, a capture process should decide what kind of document it is looking at. Getting that wrong is more expensive than misreading a field, because it is wrong at the level of what the document means rather than what it says, and downstream processing then proceeds confidently in the wrong direction.
Questions people ask about difference between receipt and invoice
Can a receipt support an expense claim?
Yes, and that is its usual role. It evidences that money was spent, which is a different question from whether an obligation exists.
Should receipts be entered into payables at all?
Generally not as payables. They belong to expense and card reconciliation, which is a separate process with a separate control.
What about a proforma invoice?
A quotation shaped like an invoice, issued before supply and not a claim for payment. It should not be entered as a payable.