The stretch from raising a purchase order to paying the resulting invoice looks like two documents and one comparison. There is a third document in the middle, produced by neither purchasing nor payables, and whether it exists decides whether the comparison can happen at all. Nearly every recurring problem in this stretch is about that middle step.
Order out, expectations set
The order records what you agreed: item, quantity, price, delivery date, terms. It is the reference point everything later is measured against, which is why vague orders produce exceptions and why the supplier's legal entity, the units of measure and what the price includes matter more than they look.
The receipt, in the middle
Whoever takes the delivery records what arrived, when, against the order line. This step belongs to operational staff who are measured on other things, which is why it is so often skipped or batched. Every day between the delivery and the receipt being recorded is a day the eventual invoice cannot clear.
Invoice in, comparison possible
The supplier bills, quoting the order reference, and the three documents are compared. Within tolerance it clears; outside it, an exception with a reason goes to whoever can resolve it. If the receipt is missing, none of this happens and the invoice takes the expensive manual route instead, which is where most payables effort is actually spent.
Questions people ask about purchase order to invoice process
What if the invoice arrives before the receipt?
It waits, which is why receipt timeliness matters as much as receipt existence. This is a common and entirely avoidable cause of delay.
Who should own the receipt step?
Whoever physically takes the delivery, with a tool that makes it take seconds. Ownership has to follow usability here.
Does this apply to services?
Yes, with the receipt being a confirmation that the work was done by whoever commissioned it.