The full accounts payable process explained
In summary: The accounts payable process moves a supplier invoice from arrival to settlement and archiving through capture, coding, validation, matching, approval, posting, payment, and record keeping.
- Accounts payable owns the process from invoice receipt through to a closed, retained record. Procurement owns supplier onboarding, requisitions, and purchase orders, while goods receipt belongs to procurement/logistics depending on the goods type, payment execution belongs to treasury, and the retention obligation sits with accounting/reporting and tax.
- Most accounts payable exceptions originate upstream. An invoice that will not match usually reflects a purchase order raised with insufficient or inaccurate line-item detail, or a delivery that was never recorded.
- E-invoicing mandates require invoices to be submitted in particular formats to be considered legally valid. What those formats do not consider as mandatory information is the data needed for automation and matching.
The accounts payable process isn’t just about paying invoices on time. The lifecycle of a single invoice – let alone thousands or even millions of them – can reveal many things about an organization’s financial health. In this guide, we’ll explain what a full-cycle AP process looks like, step by step, including where AI is continuing to change the automation game and how e-invoicing fits into the AP lifecycle.
What is the accounts payable process?
The accounts payable process covers what happens to a supplier invoice between arrival and settlement: capture, coding, validation, matching, approval, posting to the ERP, payment and record keeping. It cannot be understood in isolation, because a lot of what determines whether an invoice can be processed cleanly happens upstream, before it ever reaches the AP team.
Supplier onboarding, requisition and goods receipt sit upstream and are owned by functions outside accounts payable. We are including them in this guide because these stages are where AP exceptions tend to originate. An invoice that will not match usually reflects a purchase order raised without line-item detail, or a delivery that was never recorded, rather than anything AP did.
The final stages sit downstream. Payment execution belongs to Treasury, and retention obligations run for years after the invoice has been posted and paid. Together, these stages describe the full procure-to-pay cycle.
Upstream of accounts payable
Supplier onboarding and vendor master data
Suppliers are onboarded through a controlled process that captures and validates company, tax, banking and payment information. Vendor records are then maintained centrally to support consistent data, regulatory compliance and fraud prevention across entities and regions.
Purchase requisition and purchase order
Business users submit purchase requisitions for the goods or services they need. Following the required budget and procurement approvals, an authorized purchase order is created and sent to the supplier.
Goods receipt
The receiving business unit records that goods have been delivered or services completed. This provides evidence that the supplier has fulfilled the order and supports accurate invoice matching. Not every invoice will have a goods receipt to match with. Physical goods typically will have GR while things like software and subscriptions and services will not.
Along the way, organizations must also maintain compliance with internal controls and applicable tax, financial and regulatory requirements.
The core accounts payable process (also known as Invoice-to-pay)
Invoice receipt and capture
Invoices are received through channels such as e-invoicing networks, supplier portals, email, document upload or connected procurement systems. Platforms such as Invoicetrack bring these channels together through a single intake layer, making it easier to capture and process invoices across different formats, languages, currencies and legal entities.
Invoice coding and validation for NON-PO invoices
The invoice is assigned to the appropriate company code and vendor number. Relevant accounting dimensions such as tax code, GL account or cost object can be added by data-driven extraction and recommendations, including general ledger account, cost center, tax code and other accounting dimensions. AI can pre-populate these fields using historical invoice and posting data, while validation checks that the invoice information is complete, accurate and consistent before it moves to matching or approval. Validation also helps ensure invoices comply with internal controls and applicable tax and regulatory requirements before they are processed.
Invoice matching
PO-based invoices are matched at the line-item level against the purchase order and, where applicable, goods receipt data from the ERP system. Three-way matching requires that a formal goods or service receipt has been posted in the ERP or procurement system before the invoice can proceed. Two-way matching applies where no such system receipt is required. Instead, confirmation that goods were received or services completed is captured through an approval step in the invoice workflow. Invoices within configured tolerances can continue automatically, while discrepancies are routed to the appropriate AP or business user for review.
Payment execution
Invoices are routed to the appropriate business users based on configurable approval policies, such as management responsibility or cost center ownership. Once approved, the validated invoice is posted to the ERP system, where it is released for payment and included in the relevant payment run. Approval, posting and handoff activities remain fully traceable for audit purposes, supporting compliance with internal governance, financial controls and external audit requirements.
Approval and payment authorization
Once an invoice has been validated, approved and posted, platforms such as Invoicetrack hand it over to the ERP system. The ERP then manages its posting into the financial records, release and execution in the appropriate payment run.
Downstream of accounts payable
Reconciliation and record keeping
Payment and accounting records are reconciled in the ERP system, while invoice documents, supporting information and a complete audit trail are retained for audit and record-keeping purposes. Technology providers can support this process through configurable retention, archiving and traceability capabilities, but the organization remains responsible for identifying and complying with the legal, tax and regulatory requirements that apply in each jurisdiction.
PO and non-PO invoices follow different paths
Whether an invoice references a purchase order determines how it is validated and processed.
PO invoices follow a matching-led path. The invoice is compared with the purchase order and, where applicable, the goods receipt to confirm that the supplier, quantities, prices and delivery information are consistent. A decision engine can apply the organization’s specific tolerance rules to determine whether the invoice can proceed automatically or requires review. In this case, the exceptions, such as price differences, missing goods receipts or quantity discrepancies, are routed to the appropriate person for resolution.
Non-PO invoices do not have a purchase order or goods receipt to match against and instead follow a coding and approval-led path. AP typically assigns the general ledger account before routing the invoice for approval. The approving business user – the person who ordered the goods or services – then assigns the relevant cost object, such as cost center, WBS element, or internal order. Approval policies may be based on factors such as organizational responsibility, cost ownership, or invoice value.
In both paths, automation can support validation, routing and exception handling. However, the customer remains responsible for defining its purchasing policies, matching tolerances, approval structures and compliance requirements. Technology applies the rules configured by the organization but does not determine whether those rules satisfy applicable legal, tax, accounting or internal control obligations.
The controls built into the process
Every step in the AP process is about fulfilling two goals: getting the invoice posted and paid, and making sure that it should be paid at all. There are four controls across the cycle, and their purposes range from fraud prevention to audit defensibility.
Segregation of duties
Segregation of duties means no one person can post an invoice and complete its payment entirely on their own. The principle splits the cycle into duties that must be held by different people or, at minimum, different roles.
Approval thresholds and delegation of authority
A delegation of authority framework is a list of people who can approve spending and up to what value. A team lead might be able to approve invoices for up to 5,000 euros whereas a finance director can approve considerably more.
Vendor master change controls
A vendor master change control governs who can create and/or edit a supplier’s record in the ERP, and it exists mainly for one field: the bank account. Separating the ability to edit bank details from the ability to release payment is an essential fraud prevention control.
Matching tolerances and duplicate detection
Matching tolerances define how much variance between an invoice and purchase order can be accepted without review. Set too tightly, they create unnecessary exceptions, but set too loosely, and they can allow overbilling to pass unchecked.
Duplicate detection identifies invoices that may already have been received by comparing supplier, invoice number, amount and other key details. This ultimately helps prevent duplicate payments whether submitted by accident or intentionally.
Common accounts payable exceptions
An AP exception occurs when an invoice cannot move smoothly from receipt to payment and requires investigation, correction, or approval before processing can continue.
Common exceptions include:
- Missing purchase order (PO)
- Invoice amount does not match the PO
- Quantity mismatch between invoice and purchase order and/or goods receipt
- Missing goods receipt
- Duplicate invoice
- Incorrect vendor details
- Missing tax information
- Invalid coding or cost center
- Missing approver
- Invoice outside policy or spending limits
In a manual environment, these invoices often end up in email inboxes, spreadsheets, or disconnected queues while AP teams work out what happened and who owns the next step. Exceptions can result in delayed payments, higher processing costs, reduced visibility, and increased compliance risk.
Modern AP automation platforms are designed not only to process invoices, but also to manage exceptions in a controlled and auditable way. They help prevent avoidable exceptions through automated data capture, validation, matching, duplicate detection, and business-rule enforcement. When an exception cannot be resolved automatically, it is seamlessly routed to the appropriate person or team with clear visibility into the issue and the action required.
Invoicetrack follows this approach by combining automated validation, configurable business rules, purchase order and goods receipt matching, structured exception workflows, and full auditability. Rather than allowing invoices to disappear into unmonitored queues, the platform ensures that every exception has a defined status, owner, and resolution path.
Equally important, exception data can be used to identify recurring process issues. By analyzing exception patterns across suppliers, business units, entities, and document types, organizations can address root causes such as poor master data quality, procurement process gaps, or approval bottlenecks. This shifts exception management from a reactive activity to a continuous improvement strategy. Invoicetrack’s analytics layer, Beachwalk, supports this by providing visibility into exception trends, automation blockers, workflow bottlenecks, and process performance over time.
How e-invoicing is changing accounts payable processes
Governments around the world are passing laws requiring companies to send and receive invoices in specific formats, through government platforms, certified service providers or via direct connections. While the objective of these mandates is typically to improve tax compliance and reduce the VAT gap, they’re also changing how accounts payable teams process invoices.
- More invoices are arriving in structured formats: Traditional paper and pdf invoices are rapidly being replaced by structured formats such as XML, which is very helpful for faster data exchange but requires AP teams to adapt their workflows and tech landscape.
- Compliant electronic invoices do not automatically improve AP efficiency: An invoice can be fully compliant with an e-invoicing mandate while still lacking the information required for automated matching, coding or approval
- AP teams face mounting cross-border complexity: The global mandate landscape is evolving all the time and multinational organizations and their shared services must learn to manage an increasingly complex compliance landscape
For a deeper look at global mandates, VAT compliance requirements and the operational impact of e-invoicing, see our dedicated compliance and e-invoicing resources.
How to measure the accounts payable process
The performance of a team’s accounts payable process can be measured across several categories, including speed, cost, accuracy, cash and working capital and more. We go into significant detail on the topic of accounts payable KPIs in this article.
Where automation and AI fit in the accounts payable process
Automation handles the predictable parts of accounts payable: invoice capture, extraction, validation, matching, approval routing, duplicate detection, and ERP posting. In Invoicetrack, configurable business rules, matching logic, and workflow controls allow compliant invoices to move through the process automatically, while exceptions are routed to the appropriate person for resolution. Every automated action, workflow decision, and exception resolution is recorded in an auditable decision trail – meaning the system behaves consistently, transparently, and in line with configured rules.
AI extends this further, primarily in the capture, coding, and matching stages. By learning from historical invoice and posting data, it can improve extraction accuracy, recommend coding decisions, and reduce exceptions. Critically, AI recommendations in AP are assistive, and every suggestion needs to be traceable, reviewable, and subject to human approval when configured as necessary.
Human judgment remains essential for complex matching discrepancies, missing information, commercial decisions, and supplier disputes. The goal is not to replace people, but to automate routine work so AP teams can focus on exceptions and oversight.
FAQs
Nine stages make up the full cycle: supplier onboarding, purchase requisition and purchase order, goods receipt, invoice receipt and capture, coding and validation, matching, approval and payment authorization, payment execution, and reconciliation and archiving. The first three sit upstream and are owned by procurement/sourcing and/or procurement/logistics. Payment execution is owned by treasury and reconciliation and archiving is typically managed by accounting/reporting and tax.
Accounts payable owns the operational invoice-to-pay process, while long-term retention and archiving responsibilities are shared across the organization.
Two-way matching compares the invoice to the purchase order.
Three-way matching compares the invoice, purchase order and goods (or service) receipt to confirm the supplier delivered what they billed for.
Three-way matching is mainly used for physical goods, while services and subscriptions are usually matched two ways or handled as non-PO invoices.
A non-PO invoice arrives without a system purchase order to match against, so it cannot be validated by matching. It follows a coding and approval path instead: AP assigns the general ledger account – either automatically via configured rules or manually – before routing the invoice for approval. The approving business user then assigns the relevant cost object, such as a cost center or WBS element. Non-PO invoices carry more manual effort and more control risk than PO invoices, which is why most organizations track the proportion of each.
Top-performing AP teams process invoices requiring workflow approval in around three days from receipt to posting, while the average is 8.2 days.
Invoices that three-way match successfully can post automatically with no meaningful delay. Cycle time definitions vary but most organizations measure from invoice receipt to posting or approval, not to payment.
Payment timing is a treasury decision driven by payment terms, and the relevant AP metric is on-time payment: whether invoices are paid in line with agreed terms, not how quickly.
No. E-invoicing mandates require invoices to carry the data tax authorities need, such as VAT registration numbers, tax codes, and buyer and seller identifiers. Automatic matching requires different data: purchase order references, delivery note numbers, units of measure that align with the buyer's system, and line descriptions that match master data.
Mandates do not typically require any of these things, so a compliant invoice can still need manual intervention.