The straight-through processing rate (STP rate) is the share of transactions, such as supplier invoices, that a process handles from receipt to posting or payment without any manual intervention. In accounts payable it is also called the touchless processing rate.
The straight-through processing rate is calculated as follows: STP rate = transactions processed with no human touch, divided by total transactions processed, multiplied by 100. An invoice counts as touched as soon as someone edits a field, resolves an exception, adds a code or reroutes it. A team that processes 2,000 invoices a month, 1,400 of them untouched, has an STP rate of 70%.
The STP rate differs from the first-pass match rate listed among accounts payable KPIs. The first-pass match rate covers the matching step only, while the STP rate covers the whole chain: capture, extraction, coding, matching, approval and posting.
A high straight-through processing rate is only good news if controls ran. An invoice that flows through untouched because nothing checked it raises the rate while paying errors faster. A more useful reading splits the rate in two:
- invoices that passed every check (price, quantity, duplicate, bank details) with no human touch
- invoices that went through untouched because no check applied to them
Reported next to the exception rate, this split shows whether automation is controlled or simply fast. It also keeps payment approval meaningful: approvers focus on exceptions instead of signing every invoice.
Phacet raises the STP rate by the controlled route. Agents check every invoice against purchase orders, delivery notes, contracts and supplier data, so clean invoices pass untouched and only discrepancies reach a person, in line with exception-based finance review. The agent that validates invoices before payment logs each decision, so the rate can be audited invoice by invoice.
