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A purchase order process gives finance and procurement teams control over spending, from the initial request through to delivery and invoice payment. Learn how to streamline approvals, improve three-way matching, reduce errors and fraud, and build a more reliable audit trail with the right processes and technology.
Key takeaways
In an ordinary English B2B transaction, a purchase order may form part of a legally binding contract, depending on its wording and how the parties respond in context.
Three-way matching checks whether the supplier invoice matches both the PO and the goods received note before payment. HMRC's GfC8 guidance describes a two-way match, or a three-way match including the goods received note, as a key procure-to-pay control.
Organisations approve only 28% of invoice line items through three-way matching against a median 85% PO-to-invoice match rate, according to APQC's research covering 470 companies. This means most teams still rely on the weaker two-way check and leave a significant compliance gap.
Automating the process removes re-keying and spreadsheet matching, reducing manual data entry and making invoice matching easier to manage at scale.
A purchase order is the buyer's formal record of what it wants to buy and from whom. It also records the terms. Its contractual effect depends on the wording and circumstances, including the parties' conduct.
The purchase order process starts with an internal requisition and ends with invoice reconciliation, covering supplier fulfilment in between. It ensures finance approves commitments before money moves rather than discovering them afterwards.
Most teams feel its absence at month-end. Invoices arrive with no order number, while purchase orders sit in spreadsheets that nobody reconciles. Finance discovers off-process spend only after paying the invoice. In Efficio's 2025 survey of 300 senior finance and procurement leaders across the UK, Germany, the Nordics, and France, at companies with £1bn+ in sales, 93% said maverick buying materially contributes to cost leakage.
A reliable PO process starts with clear approval and contract formation. Receipt and invoice-matching controls then connect the order to payment. The legal, tax, and regulatory information in this article reflects published guidance available at the time of writing. It is general information, not legal or tax advice, and specific requirements can vary depending on the transaction and business circumstances.
UK public bodies increasingly require suppliers to quote a PO number, and some private organisations are adopting the same approach faster than researchers have measured. Under a “No PO, no pay” policy, accounts payable teams return invoices that lack a valid purchase order number. These policies now run across NHS Wales, since 1 September 2018 and amended in June 2024. Councils including Norwich, from October 2024, and Caerphilly, from July 2024, also use them. The University of Edinburgh has done so since October 2023.
No current survey quantifies private-sector adoption. Suppliers that sell to public bodies with these policies already handle PO-first billing, and scaling UK and European finance teams increasingly ask the same of their own buyers.
What is a purchase order and how does it work?
A purchase order, or PO, is a formal document a buyer sends to a supplier setting out the proposed purchase. Depending on its wording and the parties' actions, it may form part of the contractual arrangement. The contractual effect of a purchase order depends on its wording and the circumstances of the transaction. This article focuses on the operational process rather than legal interpretation. The CIPS glossary defines it as “a commercial document issued by a buyer to a seller confirming the goods or services required together with the quantity and specification needed.”
The buyer raises and approves the PO internally, then sends it to the supplier. After the supplier accepts and fulfils the order, it issues an invoice quoting the PO number. Finance then matches the invoice against the order and delivery record before payment, assigning the same PO number to every document in the chain to give the team an auditable record.
What information should a purchase order include?
A well-structured purchase order usually includes two groups of information. Gaps in either can cause matching failures later:
Order-level details: Identify the order with a unique PO number and issue date. Name the buyer's legal entity and billing address, along with the supplier's name and address. Add the delivery address. Record payment terms and delivery terms, including an Incoterms rule for international orders. Specify the total value and currency, and include the authorised signature or approver reference.
Line-item details: Identify each item with a description or SKU and record its quantity and unit price. Add the VAT treatment and expected delivery date per line.
Businesses should retain the complete PO-to-payment record according to their internal record-retention policy and any applicable legal requirements.
What are the steps in the purchase order process?
Finance and procurement teams move each purchase through seven steps, from internal request to reconciled payment:
Requisition: An employee or department raises an internal request that explains the need and identifies the cost centre with its budget.
PO creation: Finance or procurement converts the approved requisition into a purchase order with a unique number.
Internal approval: The procurement system can route the PO by amount. Cost-centre and category rules determine the right approver.
Dispatch: The buyer sends the approved PO to the supplier, usually as a PDF or through a supplier portal.
Supplier acceptance: The supplier confirms acceptance in writing or begins fulfilment. Keep any written confirmation with the purchase order.
Goods receipt: The receiving team records delivery against the PO, typically as a goods received note or delivery note.
Invoice reconciliation: Finance matches the supplier's invoice against the PO and receipt before authorising payment.
Speed through the first four steps is measurable. Across APQC's benchmarks covering 1,250 companies, the median cycle time from requisition receipt to PO release is 2.0 days, with top performers issuing in about one day. APQC's global, cross-industry cost-per-PO benchmark is a median $55 USD, so a slow process is expensive as well as frustrating.
What are the types of purchase orders and when should you use each?
Four purchase order types reflect how certain the buyer is about the purchase details and delivery schedule. The taxonomy originated in purchasing application documentation rather than a standards body, but procurement systems commonly use these categories:
Type | Cost driver | Best use case |
|---|---|---|
Standard purchase order | Fixed price and quantity for a single order | One-time purchases where the buyer knows the items, quantities, costs, and delivery dates |
Planned purchase order | Long-term commitment to quantities and estimated costs, with tentative delivery schedules | Recurring supply from a single source where delivery dates will firm up later |
Blanket purchase agreement | Negotiated prices for a period, although the buyer has not fixed a delivery schedule | Repeat buying from one supplier at prices the buyer and supplier agreed in advance |
Contract purchase agreement | Terms and conditions only; the agreement does not specify goods or services | Agreeing legal terms now, then issuing standard POs against the contract later |
CIPS uses different vocabulary for the same instruments. Its glossary defines framework agreements and call-off contracts. Its Global Standard treats blanket orders and framework agreements as equivalent. Expect supplier paperwork to mix both sets of terms.
What's the difference between a purchase order and an invoice?
A purchase order is a buyer-issued document that sets out a proposed purchase, usually before delivery. An invoice is the supplier's request for payment, which the supplier issues after delivery or according to a billing schedule the parties agreed. The two documents sit at opposite ends of the same transaction:
Purchase order | Invoice | |
|---|---|---|
Who creates it | The buyer | The supplier |
When the buyer or supplier issues it | Before the supplier provides the goods or services, in most cases | After the supplier provides them or according to the billing schedule the parties agreed |
Purpose | Records what the buyer intends to purchase, including quantities and prices, plus delivery details | Records what the supplier is charging for and the amount due |
How Finance uses it | Checks the approved purchase and committed spend | Verifies the amount payable and processes the payment |
The invoice is the document Finance uses to verify the amount payable and complete the accounting process. The PO records the approved purchase and gives Finance a baseline for checking whether the invoice matches what the buyer ordered.
What's the difference between a purchase requisition and a purchase order?
A purchase requisition asks permission to buy; a purchase order commits the company to buy. The requisition remains internal and records the business need against its cost centre and budget before the business applies its approval authority.
Budget-owner approval at the requisition stage gives the subsequent PO its internal authority. The supplier receives one clean document rather than a request that might still face rejection. Teams that skip requisitions and approve POs after dispatch end up negotiating with suppliers about orders that lacked internal sanction.
How does three-way matching connect the PO to payment?
Three-way matching checks whether the supplier's payment claim matches the order authorisation and delivery evidence before finance authorises payment. The purchase order provides the baseline, while the goods received note or delivery note records delivery. Finance checks both against the supplier invoice.
Two-way matching drops the receipt and checks only the PO against the invoice. Software runs matching per line with configurable tolerances. When a discrepancy exceeds tolerance, the matching system places the invoice on hold until someone reviews it.
Three-way matching is a common accounts-payable control. The exact matching rules and tolerances depend on the company's process and system configuration.
In APQC's benchmark dataset, organisations match a median 85% of supplier invoices with a PO, yet approve only 28% of invoice line items through three-way matching. Finance teams can read that gap as evidence that most organisations rely on two-way PO matching rather than full three-way matching. For your workflow, this is an opportunity. Adding receipt verification to your existing PO match catches discrepancies earlier and strengthens invoice controls without rebuilding your process from scratch.
Organisations that leave invoices outside three-way matching face fraud exposure. Billing schemes made up 21% of occupational fraud cases in the ACFE's 2026 Report to the Nations, covering 2,402 cases across 143 countries, with a median loss of $90,000 and a median 14 months before detection. Three-way matching can flag an invoice when it lacks a valid PO or receipt, although no single control catches every fabricated invoice.
What are the benefits of using purchase orders?
Each benefit of a purchase order process maps to a specific failure it prevents:
Budget control: An approved PO records committed spend before the invoice arrives, so budget owners can review the remaining budget context rather than payments Finance has already made.
Audit trail: The invoice sits in a single evidenced chain with the authorising PO and its delivery note. This creates a consistent audit trail for internal review and supplier queries. It also supports month-end reconciliation. A “No PO, no pay” rule, which the UK public bodies above have adopted, makes that trail complete by construction.
Fraud prevention: ACFE researchers reported in the 2026 Report that a lack or override of internal controls was present in more than half of fraud cases. They also calculated that the presence of controls cut average losses by 37%. PO matching is one of the few controls that operates before money leaves.
Spend visibility: Only 19% of European procurement and finance chiefs in Efficio's 2025 research were confident they had an accurate picture of indirect spend. Finance teams that require a PO before purchase build that picture as spend happens instead of reconstructing it at quarter-end.
In Ardent Partners' CPO Rising 2021 benchmark dataset, covering 351 procurement leaders, 70% of whom were based in North America, enterprises realise savings of 6% to 12% on every new dollar of spend that procurement brings under its control. UK teams should treat the figure as directional given the sample's geography.
When should you skip a purchase order?
Skip a purchase order when the cost of raising it exceeds the risk it controls. Four situations usually qualify:
Low-value purchases: Below a documented threshold, a company card with a preset limit gives better control per pound of admin than a PO the team will not match.
Genuine emergencies: Buy first, document immediately after, and review why the emergency route was needed so it stays rare.
Master service agreements: Where a signed contract already fixes prices and terms, with a billing schedule also in place, a fresh PO per invoice duplicates a control the contract performs.
Recurring preferred-vendor spend: The contract governs monthly subscriptions that preferred vendors bill at contracted rates. Referencing a contract purchase agreement on each invoice provides the control without monthly paperwork.
Documenting the thresholds turns each exception into a policy decision rather than the maverick spend the organisation designed the process to stop.
What are the common issues in the purchase order process, and how do you fix them?
Five failures account for most of the pain in purchase order processes, and each has a workable fix:
Off-process buying: 85% of the senior European leaders in Efficio's 2025 research said more than a quarter of their indirect spend has no financial oversight, and 47% of UK manufacturers attributed rogue spending to poor understanding of procurement procedures, according to The Manufacturer and ServiceNow, 2023.
Fix: Make the sanctioned route faster than the workaround, with a short intake form and clearly published thresholds.Late discrepancy detection: A Forrester study surveyed 207 finance and procurement leaders; 59% said they only learn whether purchases comply with policy after the fact.
Fix: Match invoices against purchase orders on receipt, with tolerances that pass small variances and hold large ones.Manual matching at volume: The average AP team took 8.2 days to process an invoice with a 14% exception rate in Ardent Partners' State of ePayables 2025 benchmarks.
Fix: Use invoice automation for the two-way or three-way match so the team reviews exceptions instead of every line.Scattered approvals: Requests spread across email and chat leave no queue to monitor and no record of who approved what.
Fix: Centralise approval workflows so thresholds determine routing. Keep queues visible and let the system send reminders.Duplicated supplier data: Maintaining the same supplier separately in procurement and accounts payable produces mismatched records and duplicate payments. APQC's cross-industry duplicate-payment benchmark is a median 1.5%.
Fix: Keep one supplier record synchronised between procurement and AP.
Finance teams may reduce manual workload without proportional headcount growth by keeping the request and order connected to the delivery and invoice in the same system.
How does software fix manual purchase order problems?
Software fixes manual purchase order problems by holding the purchasing records together with the delivery record and invoice, rather than keeping four documents in four places. A 2023 Spend Matters analysis found that 63% of organisations relied on manual systems as their primary method for placing POs.
According to a Levvel Research study on procurement automation, automating procurement processes can cut processing costs by around 30% and improve process efficiency by 30% to 50%. For a finance team, that can mean fewer hours spent re-keying invoice data and reconciling transactions by hand.
ERP procurement modules handle PO creation and matching inside the system of record. Module names change between releases, so teams should check the vendor's documentation and the current integration catalogue before an evaluation.
Spendesk is an all-in-one spend management platform consolidating company cards, expense management, accounts payable, procurement, and budgeting. Its procure-to-pay and accounts payable tools support guided purchase requests and configurable approval workflows. They also cover purchase-order creation and supplier-invoice capture. Finance can then match each invoice to its purchase order. Finance teams gain visibility into committed spend before invoices arrive.
For a software renewal, the connected workflow has two phases:
Submit an intake form with the cost centre and category for routing to the budget owner, then send the approved PO to the supplier.
Link the invoice to the purchase order and review the match before approval. The system then routes the invoice according to the organisation's approval policy and matching configuration.
Best for: Scaling European finance and procurement teams that have outgrown card-and-expense tools but do not need enterprise procurement overhead.
Frequently asked questions about purchase orders
Can you cancel or amend a purchase order after the supplier accepts it?
Coordinate any amendment or cancellation with the supplier. Check the terms both parties agreed and keep a written record of the change.
What should an international purchase order include?
An international purchase order should state the Incoterms rule alongside the commercial details. These include currency and any customs documentation requirements. The rule assigns delivery obligations. It also determines which party bears transport risk and expense.
The current edition is Incoterms 2020, in force since 1 January 2020, with 11 rules: seven for any mode of transport and four for sea and inland waterway only. Check the customs documentation and record-keeping requirements for the goods the supplier or carrier is shipping. Account for the route and every country involved.
What is the difference between direct and indirect procurement?
Direct procurement buys what goes into the product or service a company sells, such as raw materials and components. Indirect procurement covers software and facilities. It also includes professional services that keep the business running.
Indirect is where purchase order control most often slips: in The Hackett Group's 2022 data, off-contract indirect spend was 29%.
How long should you keep purchase orders?
HMRC's VAT record-keeping guidance lists orders and delivery notes as business records and generally requires businesses to keep VAT records for at least six years. Other tax, accounting, or contractual requirements may call for longer retention.
Finance teams often start with requests in inboxes and purchase orders in spreadsheets. They then find off-process spend after payment. That is the pattern behind the cost leakage Efficio's 300 European leaders described.
Finance teams with a connected purchase order process reverse the sequence. They approve the commitment first, then connect the delivery evidence and payment record to the same PO number. Finance can decide what happens next instead of reconstructing what already happened.
For example, Spendesk customer stories include teams that reported saving up to four days per month on month-end closing after bringing purchasing and invoice work into a connected workflow. This is a customer-reported outcome, not a typical result or guarantee. Get a free tour to examine how purchase orders and matching work alongside budgets inside a spend management platform.
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Maxime Reding
Originally from Luxembourg and educated at the Rotterdam School of Management, he brings a sharp analytical mindset and a background in strategic management to our finance team. Maxime joined Spendesk in 2021 and has grown steadily through the ranks since, becoming our resident finance engineer.
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