The Accounts Payable Process, Step by Step

The pile looks the same in every small finance team. A stack of PDFs in the shared inbox, a photo of a receipt someone sent from the road, a paper invoice a vendor still insists on mailing. Nobody designed it to work this way. It accumulated, one invoice at a time, until keeping track of what is owed and what has already been paid became a small project of its own.

The accounts payable process is the sequence that turns that pile into paid, recorded bills: receive the invoice, capture what it says, match it against what was actually ordered, get it approved, pay it, and record it in the books. Every business runs some version of this. Very few small teams run it on purpose.

This walks through that process stage by stage, where it actually breaks once invoice volume outgrows doing it from memory, an honest look at when three-way matching earns its keep and when it doesn't, and what the manual version is costing you in real hours a year.

What the accounts payable process actually is

Accounts payable is what your business owes suppliers for goods and services bought on credit. The accounts payable process is the set of steps that turns an invoice into cash out the door, checked, coded, and reflected accurately in your books. In a company with a dedicated AP department, each stage usually has a different person attached to it.

In a five-person company it usually means one person, often the office manager or whoever also does the books, handling every stage themselves between other jobs. There is no dedicated AP department to catch what a rushed Tuesday afternoon misses.

It is also slower and more expensive than most owners assume, because nobody has ever timed it. According to Ardent Partners' Accounts Payable Metrics that Matter in 2025 (February 2025), the average organization spends $9.40 and 9.2 days to process a single invoice, and 14% of invoices still trigger some kind of exception along the way.

The accounts payable workflow, step by step

The accounts payable workflow is the same six stages whether you run it from a spreadsheet or a system built to handle it automatically. Naming them clearly is most of the battle, because the pile stops feeling like chaos once every invoice has a known place in the sequence.

1. Receive the invoice. It arrives by email, portal, or paper, from a vendor whose format you don't control.
2. Capture the details. Vendor, invoice number, PO reference if one exists, line items, amount, and due date get pulled onto a record you can actually search.
3. Match it against a purchase order and receipt. Check the invoice agrees with what was ordered and what showed up, when a PO exists at all.
4. Route it for approval. The person who can confirm the spend was legitimate signs off, at a threshold that fits the amount.
5. Schedule and make the payment. Pay on the date that keeps terms and cash both intact, not the date someone finally notices it's overdue.
6. Record it in the books. Post the entry, code it to the right account, and close the loop so the aging report reflects reality.

Where this breaks in a small finance team

None of these six stages is hard on its own. What breaks a small team is doing all six, for every invoice, without a single system holding the state between them. Here is where it actually goes wrong, stage by stage.

Every one of those breaks the same way: a step that depends on someone remembering, on a busy day, with no record of what already happened. That isn't a discipline problem. It's what happens when a six-step process runs on memory instead of a system.

Invoice matching: two-way, three-way, and when three-way is overkill

3 way match means checking the invoice against both the purchase order and the goods receipt, confirming what you were billed for is what you ordered and what actually arrived. It's the standard for manufacturers and distributors carrying physical inventory, and it catches a real problem: being billed for 500 units when only 480 showed up.

Three-way matching also assumes you have goods receipts to match against in the first place: a record of what physically arrived and when. If nobody logs receiving, three-way match is a policy with nothing to check it against, and it quietly turns back into no match at all.

The honest answer for most service businesses, agencies, and small retailers is two-way match, or no formal match at all for recurring fixed-cost bills like rent and utilities. Match the process to the risk on the invoice, not to what a textbook says every business should do.

What the pile is costing you: a worked example

Say your team processes 400 invoices a month, and each one takes 12 minutes on average from the moment it lands to the moment it's filed and coded: opening it, keying the details, checking it against a PO where one exists, and chasing an approval. At a loaded cost of $38 an hour for the person doing it, here's what that adds up to.

Four hundred invoices at twelve minutes each is 80 hours a month, roughly two full working weeks, spent on data entry and chasing rather than anything that grows the business. Run your own invoice volume and hourly cost through the labor cost calculator to see what your version of this number actually is.

That figure is only the labor. It doesn't include late fees, missed early-payment discounts, or the cost to a vendor relationship of paying consistently late, all of which tend to show up once someone finally adds up what the manual process is actually costing.

The invoice approval workflow that actually holds up

A working invoice approval workflow has one job: get the right person to say yes, once, without the invoice sitting in someone's inbox for two weeks. The two things that break it are a chain that's too long for the amount involved, and no fallback when the approver is out.

Set a dollar threshold. Most invoices under it get approved by whoever owns the vendor relationship, no chain required. Above it, add a second approver. Give every approver a backup, or every invoice above the everyday amount will eventually wait on one person's vacation.

The same Ardent Partners report breaks its findings out by performance tier. The top 20% of AP teams, what it calls Best-in-Class, run a visibly different process from everyone else:

The gap isn't a mystery. Best-in-Class teams get there by removing exactly the manual, memory-dependent steps this post has been describing: automatic capture and matching, defined approval thresholds, and payments that go out on a schedule instead of when someone remembers. That's the same reasoning behind the agents we build for document intake, and the automation ROI calculator will tell you whether closing that gap pays for itself at your volume.

It's also the same capability behind SmallERP, which reads receipts and invoices, codes them to the right account, and keeps the books clean without someone typing every line by hand.

Frequently asked questions

The bottom line

The accounts payable process isn't complicated. Six stages, one owner, and a way of checking that nothing depends on a single person's memory. What's expensive is running it manually past the point where your invoice volume can still fit in someone's head alongside their real job.

If the worked example above sounds like your numbers, or you're not sure whether three-way matching is actually buying you anything, bring the real invoice volume and process to a call. We'll tell you honestly whether automating the boring part is worth it before you spend anything building it.