Accounts payable software vs accounting software: do you need both?

Separate the accounting record from the work before it

A supplier invoice needs both an operational decision and an accounting record. Someone must establish whether the supplier, goods or services, amount and coding are correct. The business must then record the liability and keep payment and reconciliation records consistent.

Use this as a responsibility map, not a claim that every AP product supports every row. In particular, two-way matching compares an invoice and purchase order; three-way matching also includes receiving evidence. ArrowBill offers two-way PO matching on Team.

Check what Xero or QuickBooks already provides

Accounting systems are not simply blank ledgers. Xero's UK bill-management page describes bill entry, bill tracking and payment features. Intuit's UK AP automation guidance describes uploading bills, extracting information and reviewing it before saving; availability depends on the account and rollout.

Before buying another application, run a few real invoices through the tools available in your own subscription. Check the exact approval options, user permissions, document handling and purchasing support. Features advertised for another country or edition may not describe your account.

Ask the person who actually prepares bills to do the test. A feature can exist but still leave too much manual work for your document types. Conversely, a modest change to the current process may solve the problem without an extra subscription.

When your accounting system may be enough

Consider staying with the existing setup when one responsible person handles a manageable invoice queue, source documents are retained with the bills and approvals can be evidenced clearly. The important question is whether the process works reliably at your volume.

• Invoices reach a known inbox and are entered promptly.
• Reviewers can check the source, supplier, amounts and coding without reconstructing information.
• The business can identify who authorised a purchase or bill.
• Duplicate checks and payment controls are understood.
• Absences do not leave finance unable to find decisions or documents.

There is no universal invoice count that makes a separate product necessary. Fifty complicated invoices across several departments can demand more coordination than a larger set of predictable monthly charges.

When a separate AP workflow can be useful

You repeatedly rebuild line items

If one invoice contains several departments, projects or purchases, a total-only entry may leave substantial coding work. Test line-level extraction and review with the invoice capture evaluation guide.

Approval is spread across email threads

A dedicated queue can make ownership and status clearer. Test the rules you need: value thresholds, more than one approver, absence cover and what happens when nobody matches a route. The invoice approval workflow guide explains the individual steps.

Exceptions disappear between people

A missing PO, disputed line or unknown supplier needs an owner and a next action. If staff maintain a parallel spreadsheet just to track these questions, assess whether the proposed AP system makes that register unnecessary.

Your approval boundary needs to be clearer

Agree whether a bill is published before or after approval, what changes require another decision, and who can bypass the normal route. An additional application helps only if those boundaries are configured and understood.

Example: a supplier bill with three department owners

Imagine a fictional UK business receiving a £1,800 supplier invoice covering three departments. Finance can record that bill in its accounting system. The coordination problem is confirming each department's charge and retaining the decisions before the final coding is published.

1. Capture the invoice once and keep the original document.
2. Review the supplier, reference, lines and totals.
3. Route the relevant review to the authorised department owners.
4. Resolve a disputed line without losing the other decisions.
5. Publish the reviewed bill with agreed coding into the correct accounting company.
6. Use the existing payment and reconciliation process to settle it.

That is a test scenario, not a claim that all software supports line-specific approvals. Ask the vendor to demonstrate the exact route your business needs. Check the final bill and history, including what happens if the amount changes after someone has approved it.

For the integration checks behind this handoff, use our Xero and QuickBooks AP automation guide.

Make the extra subscription justify itself

Write down three current problems and a pass condition for each. For example: finance should see the owner of every pending invoice; a multi-page bill should retain all required lines; every published record should be traceable to one accounting bill.

Run the same sample through your current process and the proposed alternative. Compare active handling time, corrections, approval visibility and ongoing administration. Use the UK AP software cost guide to turn the results into a budget.

ArrowBill captures and reviews supplier invoices and publishes bills to Xero or QuickBooks Online. Team adds approval workflows and two-way PO matching. Your accounting platform remains the ledger, and supplier payment remains outside ArrowBill.

If those functions address your gaps, include it in a trial. If you are comparing several providers, our small-business AP software comparison sets out documented capabilities and limitations.

Frequently asked questions