In manufacturing, the cost of accounts payable is set by purchasing, not by invoice volume.
Parts get bought at the plant. Equipment work gets approved by a plant manager. Raw materials get ordered by procurement against a contract. Freight arrives from a carrier nobody in finance has spoken to. Each of those purchases is a commitment made outside the accounting system, and the invoice shows up weeks later with none of that history attached. AP then spends its time reconstructing decisions other people already made.
For finance leaders, the cost of that reconstruction rarely appears as an AP line item. It shows up as understated capital projects, received-not-invoiced balances that complicate close, purchase price variances nobody can explain, and a team that grows with transaction volume because there is no other way to keep up.
How Manufacturing Purchasing Differs
Most AP guidance assumes a single office, a manageable vendor list, and purchases that originate at a desk. Manufacturing breaks all three assumptions.
Purchasing is distributed across the plant floor, the field, and corporate, so the person who makes a commitment is usually not the person who approves the invoice or owns the GL code. Goods receipt is a physical event recorded by someone whose primary job is not accounting, which means quantity discrepancies get resolved on a dock before finance hears about them. And the invoice mix is unusually wide: raw materials, MRO supplies, tolling and subcontract services, freight, utilities, capital equipment, and professional services all land in the same queue with different reviewers, different coding logic, and different documentation requirements.
Quincy Recycle runs into all three. The company operates eight recycling facilities across the Midwest plus Quincy Farm Products, which converts food byproducts into animal feed, and processes more than 1,000 invoices a month across two entities. The number of places a purchase can start is what makes accounts payable for manufacturing expensive.
Three-Way Match Against Partial Receipts
Three-way match is simple in theory: purchase order, goods receipt, invoice. In a plant environment it rarely lines up cleanly.
A PO for 500 units arrives as 300 now and 200 in three weeks, producing two invoices against one order. That requires matching against the item receipt rather than against a single delivery event, with a running received quantity that both invoices draw down. Unit-of-measure differences compound it. The PO says pallets, the receipt says cases, the invoice says pounds, and the match fails silently unless conversion is handled. Blanket POs against annual agreements add a third variation, since what matters is remaining balance rather than line-by-line reconciliation of one document.
Then there is the question of what counts as a discrepancy at all. Bulk and commodity purchases produce over-shipments and under-shipments constantly. Deciding that a 3% price variance or a small quantity difference is acceptable should be a documented policy applied by the system, not a judgment call an AP specialist repeats forty times a month. Setting three-way match tolerances in advance is what separates exception handling from re-adjudicating the same decision.
Freight, Variances, and Inventory Cost
Three consequences follow from imperfect matching, and each one lands on the financial statements rather than in the AP queue.
Understated inventory. Under standard inventory accounting, the costs of bringing goods to their present location and condition are capitalized into inventory rather than expensed. The freight invoice usually arrives separately, from a different vendor, after the goods invoice has already been coded and closed. If freight-in cannot be traced back to the receipt it belongs to, it ends up in a general expense account and inventory is understated.
Unexplained purchase price variance. In standard-cost environments, the gap between standard and actual purchase price posts to PPV. When the PO price, the receipt, and the invoice are reconciled in three different places, the variance is real but unexplainable, and someone in finance spends part of every close working backward through invoices to account for it.
Received-not-invoiced balances that never clear. The accrual is only as good as the receipt data behind it. A GR/IR balance that does not resolve is a month-end close problem first and an audit finding eventually.
MRO and Tail-Spend Volume
Maintenance, repair, and operations purchasing is where most of the disorder originates.
MRO spend is high in transaction count, low in value per transaction, and urgent by definition. A line goes down, a technician drives to a local supplier, and the commitment is made before any system knows about it. The PO, when one exists, gets created after the fact to justify an invoice that already arrived.
What accumulates is a long tail of vendors used once or twice, each generating an invoice that costs more to process than the purchase was worth, along with duplicate vendor records and suppliers nobody vetted. Two changes reduce the volume, and a third reduces the risk. Mobile purchase requests let a technician generate a real PO from the supplier parking lot instead of writing a number on a work order. And routing low-dollar, high-frequency purchases to virtual cards with preset controls keeps them out of the PO workflow entirely. Disciplined vendor record management then stops the tail from becoming a duplicate-payment risk.
Capital Projects and Component Invoices
Capital purchases almost never arrive labeled as capital purchases.
A new production line gets assembled from dozens of invoices spread across months: components, freight, installation labor, controls, and commissioning. Individually most of them look like ordinary maintenance spend and fall below the capitalization threshold. Collectively they are a fixed asset. This matters for tax as well as book treatment, because the IRS de minimis safe harbor under the tangible property regulations is applied per invoice or per item, which is exactly the level at which the aggregation decision gets lost.
If project attribution is not captured during coding, someone rebuilds it at quarter end from GL detail and memory. Quincy Recycle handles this with custom fields that flag purchases tied to capital projects, including small purchases that roll up into larger equipment investments, so project totals accumulate as invoices are coded rather than being reconstructed afterward.
Approval Authority Across Multiple Sites
Approval routing in manufacturing is a matrix, not a chain. Authority varies by dollar amount, by spend category, by site, and sometimes by project. A plant manager may approve maintenance spend to a threshold but not capital equipment. A fixed asset accountant needs to see equipment invoices an AP clerk should not have to interpret.
Two design decisions carry most of the control value. The first is approving the request rather than the invoice, since approval at requisition is a control and approval at invoice is a formality with the money already committed. The second is routing by what the invoice is instead of when it arrived. Building category-based approval routing into the workflow removes the daily triage that otherwise falls to one person’s judgment.
Quincy Recycle uses role-based trays that direct invoices to AP staff, fixed asset accountants, and equipment specialists automatically, which creates clear ownership without a manual assignment step. Designing the purchase order approval workflow with the same category logic keeps the front end and back end consistent.
Purchase Order Records Outside the System
Shared spreadsheet PO logs are common in manufacturing, and they are a control weakness rather than a shortcut.
The failure modes are predictable. Two people claim the same row. Someone buys before recording the number. A PO gets logged for a purchase that never happened, or a purchase happens against a number that was never logged. By the time the invoice arrives, the file records intentions rather than commitments, and there is no reliable population for an auditor to sample.
At Quincy Recycle, employees had to find the next available row in a shared Excel file before making a purchase, which for maintenance teams working in the field meant writing a PO number down before leaving for a repair shop. Moving that to mobile purchase requests eliminated spreadsheet POs completely and removed the duplicate and conflicting numbers that came with them. The control point moved from AP cleanup to the moment of commitment.
Validation Timing and the Payment Run
A pattern shows up repeatedly in manufacturing finance: invoices move through the process, but nothing is genuinely verified until the payment run.
When the weekly check run becomes the validation checkpoint, every exception surfaces at once, against a vendor payment deadline. Coding errors, missing approvals, and unmatched POs all arrive on the same afternoon. The team is not processing invoices at that point. It is auditing a week of them under time pressure, which is the most expensive possible way to catch an error.
Before implementing Stampli, Quincy Recycle’s AP team compared every invoice in the Thursday payment batch against its paper copy to verify coding, approvals, and payment details. Validation now happens continuously, so by the time an invoice reaches the Authorized stage the final review is already complete and payment day is execution only.
The principle generalizes past one company. Each check belongs at the earliest point where the information exists: PO validity at requisition, quantity verification at receipt, coding at capture, approval before commitment. Every check deferred past that point gets more expensive to perform.
ERP Integration in Specialized Environments
Manufacturers frequently run systems that general-purpose AP tools were not designed against: industry-specific platforms, heavily customized deployments, and systems a decade or more old.
Quincy Recycle runs RIMAS, a specialized ERP built for the recycling industry, with invoices flowing through Stampli and synchronizing back while RIMAS remains the financial system of record. That division is worth stating explicitly. The AP platform owns the workflow around requests, approvals, coding, and documentation. The ERP owns the books.
Quincy Recycle runs both operating entities through the same connected process. That last question is worth confirming before signing rather than after.
Capacity Without Additional Headcount
At manufacturing volumes, manual data entry becomes a throughput ceiling rather than an inconvenience.
Stampli AI identifies vendors and populates invoice information ahead of review, covering 2,700+ unique ERP-aligned fields and automating 87% of finance work with human review retained on approvals and exceptions. At Quincy Recycle, that means more than 20,000 invoice fields populated across roughly 1,000 invoices in an average month.
The financial argument is not the time saved on data entry. It is what that capacity substitutes for:
“If we didn’t have Stampli, we probably would have needed to hire another person. Instead, we’re able to get through more invoices with the team we have, and that gives us time to focus on improving other processes.”
Kelsey Hayes, Financial Controller at Quincy Recycle
For a growing manufacturer, that is the difference between AP headcount scaling with transaction volume and AP headcount staying flat while the business grows.
What Connecting Procurement and AP Requires
The sequence matters more than the software when moving toward a connected procure-to-pay process, and most of the work is design rather than configuration.
- Map where purchases actually begin. Include field maintenance and any buying that happens outside procurement today. Workflows built only around planned purchasing miss the spend that generates the most AP work.
- Move PO creation to the point of commitment. After-the-fact POs stop being necessary once a real one can be created in the moment.
- Document approval authority before configuring anything. Thresholds by site, by category, and by amount.
- Set matching tolerances as policy rather than practice. One documented decision applied consistently replaces forty individual judgment calls a month.
- Capture project and asset attribution during coding. It costs nothing at capture and saves a reconstruction at close.
- Verify the ERP sync before signing. Field level, entity level, and failure handling.
Read the full Quincy Recycle case study, or see how Stampli supports manufacturing AP operations.
