--- title: "A customer has paid twice: checking an overpayment before any refund" canonical: https://www.billabex.com/en/blog/customer-double-payment-overpayment-refund/ lang: en alternate: https://www.billabex.com/fr/blog/client-paye-deux-fois-trop-percu.md updated: 2026-10-18 index: https://www.billabex.com/llms.txt --- # A customer has paid twice: checking an overpayment before any refund Two payments for the same amount appear on the customer account. Sales proposes an immediate refund to preserve the relationship. Accounting first wants to establish whether there are actually two bank transactions, whether the second payment covers another invoice and whether a bank return has already been requested. Those checks have a specific purpose: return the correct amount to the correct party, once. They should not become a reason to retain an established overpayment. A confirmed duplicate receipt calls for prompt resolution, a clear explanation to the customer and an updated record that prevents further reminders for the paid invoice. The operational approach is relevant to French and European businesses. The restitution and set-off references below concern French law; apply the appropriate rules where another legal system governs the case. ## Confirm two receipts, not just two software lines Start with the bank. Two software entries can represent one transaction imported twice, a manually registered payment later synchronised, or a provisional statement replaced by a final entry. Compare references, dates, accounts and amounts with transactions actually booked by the bank. Two genuine transfers can also serve different purposes. A customer may make an advance payment and settle an existing invoice for the same amount. A central payment team may pay for several group companies. An identical description does not establish an economic duplicate. The method for tracing [cash received against an invoice still shown as open](https://www.billabex.com/en/blog/payment-received-invoice-still-open-tracing-unallocated-cash/) starts from actual transactions. Keep a link between each receipt and the evidence explaining its allocation. Asking for the second transfer's reference helps; requesting the customer's entire bank statement is rarely necessary. Also establish who noticed the issue and which facts have already been confirmed. This avoids two colleagues independently contacting the customer with different explanations. ## Recalculate within an explicit scope Consider an entirely simulated example. A €12,000 invoice, including VAT, is paid by a €12,000 transfer. Another €12,000 arrives the next day. Both receipts are confirmed, the customer acknowledges a duplicate, and this first scenario contains no other debt, advance, deduction or bank-return process. Total receipts are €24,000. The settled obligation is €12,000. The overpayment is therefore €12,000, equal to 100% of the invoice value. The account does not represent €24,000 of sales: it contains one paid invoice and additional money to resolve with accounting. In a separate variation, another €4,500 invoice exists between the same legal entities. The customer and supplier validly agree to apply €4,500 of the second receipt to it. The calculation becomes €24,000 minus €12,000 minus €4,500, leaving €7,500 to return. That agreed allocation is an explicit additional assumption, not an automatic consequence of another outstanding balance. If the second payment instead concerned an identified and agreed future order, the analysis would differ again. Record that purpose and the appropriate treatment. The team cannot simply choose whichever explanation allows it to retain the money. ## Separate restitution from set-off Article 1302 of the French Civil Code provides for restitution of money received without being owed. Article 1302-1 addresses returning it to the party from whom it was unduly received. Identify the payment and its origin rather than treating excess cash as a commercial discount or revenue. [French Civil Code, undue payment](https://www.legifrance.gouv.fr/codes/section_lc/LEGITEXT000006070721/LEGISCTA000032023808/). Set-off requires a separate assessment. Articles 1347 and 1347-1 address reciprocal obligations and, subject to particular rules, their being fungible, certain, liquid and due. A future debt or another company's receivable is therefore not simply a “deduct” button. Verify the legal basis used or record a valid agreed allocation. [French Civil Code, set-off rules](https://www.legifrance.gouv.fr/codes/section_lc/LEGITEXT000006070721/LEGISCTA000032035645/). Payer identity deserves particular attention when a parent company or service provider centralises payments. The guide to cases where [the payer is not the customer](https://www.billabex.com/en/blog/payer-versus-customer-entity-mapping/) helps retain the correct parties in the record. A contact requesting repayment is not, by itself, proof of an authorised destination. ## Coordinate the refund with bank actions Banque de France explains that an erroneous SEPA transfer cannot simply be cancelled after the bank has received the order. The originator should contact its bank promptly, and recovery is not guaranteed. This distinction makes it necessary to establish what actions have already begun. [Banque de France, SEPA incidents and disputes](https://www.banque-france.fr/en/node/303363). Ask whether the customer has contacted its bank, and check with your established bank contact for pending operations concerning the same funds. A return request is not an executed return. Equally, an accepted and completed return must be visible before another person prepares a direct refund. In our first scenario, sending €12,000 directly and also allowing a €12,000 bank return to complete produces €24,000 of outflows for a €12,000 excess receipt. The additional €12,000 becomes a new error to resolve. Coordinate one treatment route and confirm its status rather than assuming every request has already succeeded. This coordination should have an owner and a next update. Otherwise, “waiting for the bank” can become an indefinite status even when the customer has provided everything required. ## Validate the destination and follow execution through The refund record should contain the verified amount, relevant receipts, any allocation decision, the legitimate recipient and the status of bank actions. An authorised person approves the operation according to the business's arrangements. The preparer and approver need the same current calculation. If the request introduces a new IBAN, apply verification through an established channel, as described in the method for [changed bank details](https://www.billabex.com/en/blog/customer-new-iban-verification/). Claimed urgency proves neither the sender's identity nor the destination's legitimacy. Where the original payment came from a third party, clarify the route with the appropriate parties before transferring funds. Retain the refund or bank-return reference and reconcile the actual outgoing transaction. “Refund prepared” is not “refund received by the customer”. A rejected operation needs further attention. Any second attempt must take the first into account to avoid reproducing the very problem being corrected. ## Close the right issue in the customer relationship The final communication can identify the settled invoice, the acknowledged excess and the action completed. If part was allocated to another invoice, identify that invoice and the agreed amount. The customer should be able to reconcile the explanation with its own records without guessing what was offset or refunded. Stop reminders concerning the invoice actually paid, but do not automatically close every case for the customer. In the €4,500 variation, that other invoice is settled through the agreed allocation. Any additional receivables require their own assessment. A global “refunded” status does not adequately describe the whole relationship. After resolution, investigate what triggered the duplicate: the same invoice sent through two channels, an unclear reference or a reminder sent despite the first receipt. Keep that investigation factual. To connect the payments, exchanges and actions explaining the case, explore [Billabex's customer view 360](https://www.billabex.com/en/product/customer-view-360/) using an overpayment example during a demonstration. The purpose is coherent follow-up; refund execution still needs verification within your financial process. ## Sources - French Civil Code, articles 1302 and 1302-1, restitution of undue payments. - French Civil Code, articles 1347 and 1347-1, set-off and conditions. - Banque de France, FAQ on SEPA transfer incidents and disputes. Sources consulted on 7 September 2026.