Best practice in accounts payable automation is mostly a sequence rather than a set of features. Measure where the time actually goes, fix the upstream discipline that caps everything, put the record and the approval path in place, and only then buy capture and matching. Teams that follow that order get benefit at each step; teams that start with the most visible product improve the part that was already cheap.
Measure before you change anything
For a week, record per invoice how it arrived, whether it had a purchase order and a goods receipt behind it, the minutes of human attention it took and the days it waited. That measurement reorders most improvement plans and frequently identifies a free fix.
Fix what caps the ceiling
Purchase-order coverage and goods-receipt timeliness set the maximum share of invoices that can ever clear without a person. Both are policy and habit rather than software, both cost nothing, and both raise the ceiling for whatever you buy afterwards.
Put the record and the approvals in place, then capture
An invoice record with statuses, owners and ages, with approvals happening on it rather than in email, removes the largest single block of elapsed time. Capture then has somewhere to deliver and pays back immediately rather than producing images nobody can act on.
Keep the practices few enough to follow
A list of twenty best practices is a list nobody applies. Four or five, written down, with a named owner for each, is what survives a busy quarter. The ones that survive are usually the free ones: one arrival address, a status and an owner on every invoice, exceptions routed by their reason, and bank detail changes verified through a channel you already hold.
Questions people ask about accounts payable automation best practices
What is the single most common mistake?
Buying capture when the constraint is approval waiting. It produces accurate data that then sits in a queue for a week, and the elapsed time a supplier experiences does not change at all.
How conservative should the business case be?
Apply the labour saving only to the share of invoices that could actually clear without a person, which is capped by your measured purchase-order and receipt coverage. Claiming beyond that is what gets a case sent back.
Which practices are free?
Consolidating arrival channels onto one monitored address, setting a purchase-order threshold people know, and making the goods receipt somebody's explicit job at the delivery point. All three cost nothing and raise the ceiling.