The accounts payable process, step by step
Whether you call it five steps or eight, the spine is the same. Here is the full, PO-based process, the version that gives you the most control, shown end to end below.
Purchase order. The buyer issues a PO with agreed items, quantities, prices and terms, giving you a reference to check the invoice against later.
Goods or service receipt. The receiving team logs a goods receipt note confirming what actually arrived, and in what condition.
Invoice receipt and capture. The vendor sends the invoice by email, portal or paper, and AP captures and digitises it into the system.
Three-way match. The invoice is checked against the PO and the goods receipt, so you only pay for what you ordered and received.
Coding and approval. The invoice gets its general-ledger codes and cost-centre allocation, then routes to the right approvers by threshold.
Payment execution. Funds go out by ACH, wire, virtual card or cheque, timed to the terms such as Net 30 and to capture early-payment discounts.
Reconciliation and reporting. The payment clears the liability, reconciles to the bank and general ledger, and feeds accruals, aging and audit records.
Not every invoice starts with a PO. Indirect spend like utilities, subscriptions and professional services often arrives with no PO, so it skips the first two steps and routes straight from capture to approval-based review.
These non-PO invoices are a large share of the total, and the ones most likely to become exceptions.
Why an efficient accounts payable process matters
The process is not just administrative plumbing. Run well, it protects four things every finance leader cares about.
Cash flow management. A clean process gives real-time visibility into what you owe and when, so cash is never a surprise.
Discount capture. Fast approvals let you take early-payment discounts, often one to two percent, instead of missing them.
Fraud and error prevention. Matching and controls stop duplicate payments, ghost vendors and mismatched bills before money moves.
Vendor relations. Paying suppliers accurately and on time protects the commercial partnerships your operations depend on.
Payment terms and early-payment discounts
The payment step is where a good process turns into money. Terms like Net 30 or Net 60 set the deadline, but the real value is in paying early.
2/10 net 30. A 2 percent discount if you pay within 10 days, or the full amount in 30, a large risk-free return on cash.
Dynamic discounting. The discount scales with how early you pay and can adjust daily, turning AP into a lever for working capital.
The catch is speed. You can only capture these discounts if the process approves and pays fast enough to hit the early window. A slow, manual process forfeits them by default, which is one more reason cycle time and touchless rate matter.
The three-way match, explained
The three-way match is the control at the heart of the process, and the step where invoices most often stall.
It compares three documents: the purchase order (what you agreed to buy), the goods receipt (what actually arrived), and the invoice (what the vendor is billing). When all three agree on price, quantity and terms, the invoice can pay automatically; when they do not, it becomes an exception.
Tolerance limits keep small differences from clogging the queue. A variance inside a set band, say two to three percent, passes automatically, while anything outside it is flagged for review. The skill is setting tolerances loose enough to stay touchless and tight enough to catch real errors.
In our own AP shops, the fastest way to lift the touchless rate was never a new tool. It was widening PO coverage, so more invoices could be matched at all.
Exceptions come from a handful of causes:
A price or quantity difference between the invoice and PO.
A partial or over-delivery.
A missing goods receipt.
A duplicate invoice.
No PO at all, so it cannot be matched. Non-PO spend is over-represented in the exception pile.
Two-way, three-way and four-way matching
In short, two-way checks the invoice against the PO, three-way adds the goods receipt, and four-way adds a quality-inspection report.
The trade-off is control against speed. Two-way keeps low-risk invoices moving, four-way protects the ones where a defect is expensive. Setting the right level per spend category is one of the quickest ways to lift your touchless rate.
Internal controls and fraud prevention
The AP process is where money leaves the building, so it is also where fraud aims.
In the latest year about 76 percent of organisations faced attempted or actual payments fraud, and 74 percent of them were hit by business email compromise (AFP). A few controls, built into the process, stop most of it.
Segregation of duties. The person who approves an invoice must never be the one who releases the payment.
Dual authorisation. Require two sign-offs for any payment above a set threshold, such as a large wire.
Vendor master audits. Clean the vendor file regularly to remove inactive and fictitious ghost vendors before they can be paid.
Bank-detail change verification. Confirm any change to a vendor's bank details out of band, by phone to a known contact, because that request is the classic business email compromise entry point.
Positive pay. Give your bank a daily file of issued payments so it can block anything not on the list.
Worth noting, only about 17 percent of organisations yet use AI to fight payments fraud (AFP), even though spotting patterns across every invoice and vendor change is exactly what AI is good at.
The control that saved us the most, in practice, was the least glamorous one: verifying every bank-detail change by phone.
How to measure a healthy AP process
You cannot improve what you do not measure. These are the metrics that tell you whether the process is healthy, and roughly where the benchmarks sit.
Metric | What it tells you | Benchmark (Ardent Partners) |
|---|---|---|
Cost per invoice | The all-in cost to process one invoice | About $9.84 on average |
Invoice cycle time | Days from receipt to approval or payment | About 8.2 days on average |
Exception rate | Share of invoices that fail straight-through | About 18.4 percent on average |
E-invoicing share | Suppliers billing you electronically | About 57 percent |
Touchless rate | Share processed with no human touch | Best-in-class run far above peers |
Source: Ardent Partners' latest AP benchmarks. The gap between leaders and everyone else is stark: best-in-class teams process invoices at roughly 79 percent lower cost and 79 percent faster, with far more straight-through volume.
Where a manual AP process breaks down
A manual process fails in predictable ways, and every failure has a cost. If you recognise your team here, that is the case for fixing the process.
Approvals stall. Invoices sit in inboxes waiting for sign-off, which is the single biggest driver of cycle time.
Discounts slip. Slow approvals mean missed early-payment discounts, often one to two percent, left on the table.
Duplicates get paid. Without central capture, the same invoice is paid twice more often than teams admit.
Invoices go missing. Paper and emailed invoices disappear, with no audit trail of where they went.
Visibility is poor. Liabilities and accruals stay a mystery until month-end.
How to improve your accounts payable process
You do not fix an AP process by buying software first. In our experience the order that works is: fix the inputs, tighten the controls, then automate what remains.
Raise PO coverage. The more spend that runs through a purchase order, the more invoices can three-way match and pay themselves.
Centralise invoice capture. One front door for every invoice, email, portal and paper, kills lost invoices and duplicate payments.
Set sensible match tolerances. Tune the variance band so routine invoices flow through and only real discrepancies stop.
Enforce the controls. Segregation of duties and bank-change verification cost nothing and prevent the most expensive failures.
Automate matching and exceptions. The biggest lever: let AI run the match and resolve routine exceptions, so people handle only the judgment calls.
Measure it. Track cost per invoice, cycle time and exception rate, so you can prove the process is getting better.
How the process changes with your volume, ERP and vendors
The same seven steps run everywhere, but three questions decide how far to automate and how: how many invoices you process a month, which ERP you run, and whether your vendors are domestic or international.
By monthly invoice volume
Under 500 a month. A tidy manual process with good controls can be enough; automate capture to kill typos.
500 to 5,000 a month. Automate matching and approval routing, where cycle time and cost per invoice really move.
Over 5,000 a month. Agentic automation and straight-through processing pay off most, often as a managed operation.
By your ERP
Your ERP decides how cleanly automation plugs in. QuickBooks and Xero connect out of the box; NetSuite, Sage Intacct and Dynamics 365 need real two-way integration; SAP and Oracle expect deep, controlled integration, so favour a layer that is genuinely ERP-agnostic.
By domestic or international vendors
Domestic-only AP is simpler: one currency, one tax regime. If you pay international vendors, the process carries multi-currency payments, cross-border tax and more exceptions, which is exactly where automation and multi-language capture earn their place.
How automation and agentic AI transform the process
Automation does not just speed the old process up, it removes whole steps of manual work. AI captures the invoice, codes it, runs the match, resolves routine exceptions and posts to the ERP, leaving people only the genuine judgment calls.
Capture. Optical character recognition (OCR) and AI reads every invoice format, with no templates, and turns it into structured data.
Coding and matching. It assigns GL codes and runs the two and three-way match automatically.
Exception resolution. Agents investigate routine exceptions, a price variance or a missing receipt, and clear them.
Posting. Clean invoices post straight to the ERP with no re-keying.
Automated routing. Invoices route to the right approver by preset department and threshold rules, with no chasing.
System integration. The software syncs with your ERP, whether QuickBooks, NetSuite or SAP, so records update with no manual data entry.
The gains are real. In one agentic AP programme, touchless processing rose from 7 to 65 percent, invoice cycle time roughly halved from as long as 29 days to under 14, first-pass yield went from 67 to 85 percent, and on-time payment climbed from 60 to 95 percent (Genpact case study).
This is why the AP automation market is worth about $6.94 billion in 2026 and growing near 12 percent a year, on track to reach $12.46 billion by 2031 (Mordor Intelligence).
Automation does not remove the need for controls or people. Someone still owns the exceptions the system escalates, and segregation of duties still matters. What changes is that the routine majority of invoices runs itself.
Running the entire accounts payable process with AI agents
SprintAP runs the accounts payable process for you with a network of purpose-built AI agents, one per stage: capture, coding, validation, matching, exceptions and posting. The agents handle the routine flow and resolve most exceptions on their own, escalating only the genuine judgment calls.
It is built to be ERP-agnostic and keeps full audit traceability, so the controls in this article stay intact. SprintAP reports under 5 percent manual intervention and large cuts to cost and cycle time; treat those as its own figures, and test them against your baseline.
It can run as software your team drives, or as a fully managed AP operation. Because we ran multi-country AP ourselves for two decades before productising it, the conversation starts with your process, not our feature list.
For a deeper look at the software side, see our guide to AI in accounts payable. If you want the whole process run for you, that is where SprintAP fits.
