Duplicate payment
A duplicate payment happens when you pay the same invoice, or the same vendor for the same goods or services, more than once. It is usually a gap in process, not fraud. The money is still yours to recover if the vendor was overpaid.
Why duplicate payments matter in a cost review
Duplicates are one of the most common findings in a review of payments. They are easy to understand and easy to prove with records. They also point to weak spots in how invoices are received, checked and paid.
The hardest duplicates to spot are the near matches. The vendor and the amount are the same, but the invoice number was typed differently, or the invoice came through a second channel. Basic system checks look for exact matches, so these can slip through.
A plain-words illustration
Imagine a vendor emails an invoice on the first of the month. Your team enters it and pays it. A week later, the vendor sends a reminder with a different reference number, and a second person enters it as new. A paper copy arrives after that, and nobody notices it matches.
The vendor is now holding more than it is owed. It may not tell you, and it may not notice. A review comparing payments by vendor, amount and date would show the pair. You can then ask the vendor for a refund or a credit on your account.
How it shows up in a review
A partner firm reviewing accounts payable audit records often tests for duplicates across your payment history. It may compare vendor, amount, date and reference, and look for near matches as well as exact ones. [CONFIRM: a partner firm supplies and approves this statement]
Common causes include:
- Typing errors in an invoice number or date.
- More than one record for the same vendor.
- Invoices received by email, portal and mail.
- Orders without a purchase order to check against.
- A vendor resubmitting an invoice under a new number.
- A corrected invoice paid alongside the original.
A three-way match helps prevent many of these before payment. A review of past payments, such as a recovery audit, works as a backstop for those that got through.
After findings are presented, you and the partner agree how to approach each vendor. Vendors may respond with a refund, a credit or a request for support. You stay involved throughout. Recovery is not guaranteed, because it depends on the facts and on the vendor's response. Some contracts or rules also limit how far back a claim can go. [VERIFY: look-back limits in your contracts and any applicable rules]
Common mistakes
- Assuming the vendor will tell you. Vendors often do not notice credits owed.
- Only checking exact matches. Near matches are the costly ones.
- Leaving vendor records messy. Multiple records for one vendor invite duplicates.
- Accepting invoices from many channels with no single log. Pick one intake path where possible.
- Treating a credit memo as resolved. Confirm that a credit was applied and not left open.
- Blaming individuals. Most duplicates come from process gaps. Fix the process.
- Fixing only the past. Refunds help, but controls prevent the next case.
Note: If you suspect more than a genuine error, speak with counsel or your internal audit lead. This page is general information.
Related terms and pages
- Three-way match is a control that reduces duplicates.
- Recovery audit reviews past payments for errors.
- Baseline assessment records your starting terms.
- Accounts payable audit is the matching service category.
- The glossary lists more terms.
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Sources
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