“Your invoice is blocked because the purchase order number is missing.” This reply can arrive after delivery, even when your commercial contact previously confirmed that everything was in order. A firmer reminder to accounts payable will not create the missing reference. The task is to find the person who can resolve the purchasing step, then establish that the invoice is actually moving towards payment again.
There are two objectives: correct any issue in your own invoicing and avoid silently accepting a customer’s internal process as a new payment deadline. This article concerns transactions between private businesses in France. Public procurement, regulated sectors and cross-border contracts require their specific framework to be checked separately.
Did the purchase order already exist?
Start with that precise question. France’s official invoicing guidance requires the purchase order number on an invoice when the buyer previously issued one. This separates an existing reference omitted by the supplier from an order the customer never created. Service Public Entreprendre, guidance verified 11 August 2026.
In the first situation, obtain the number and verify what it covers: legal entity, service, amount and period. A reference supplied hurriedly but attached to an older engagement can cause another rejection. In the second situation, ask who will regularise the customer’s purchasing process and what originally authorised the work. Your team should not invent a reference merely to pass a software check.
Keep the agreement, accepted quotation and relevant correspondence establishing the actual order. These help distinguish an administrative difficulty from disagreement about whether the work was authorised at all. If the contact now denies ordering the service, the case has changed. The documents and the authority of the people involved need examination before continuing with a routine request for a number.
Three roles hold different answers
The operational sponsor can usually explain why the work was requested and whether it was delivered. Purchasing controls the creation or amendment of the order. Accounts payable can identify the invoice rejection and the conditions for processing it. One person may perform all three roles in a small organisation, but the functions remain different.
| Role | Information needed | Verifiable outcome |
|---|---|---|
| Service owner | Recognition of the order and delivery | Confirmation attached to the case |
| Purchasing | Reference, scope and legal entity | A checked order or reference |
| Accounts payable | Exact condition for removing the block | Invoice accepted into processing |
Direct each request to someone able to act on it. Copying ten people can weaken ownership when nobody knows what they are expected to provide. A shared exchange becomes useful when two departments give contradictory answers. In that situation, restate the facts and request a single owner for resolving the issue on the customer’s side.
Make the request actionable
Include the invoice number, date, amount, service, available contractual reference and rejection message. Then ask the missing question: “Does an order already exist, and who can provide its reference?” or “Who can regularise the order for the service that has been approved?” The wording should reflect what the evidence actually establishes.
Attach the documents needed for that decision. An invoice and the relevant section of an accepted quotation may be more useful than a complete commercial file. Do not disclose confidential correspondence about other projects to demonstrate cooperation. Where an agreed portal must be used, follow that channel while preserving a record of when and why the submission was made.
Set the next operational review. For example, ask for identification of the responsible person on the next working day, then confirmation when the document has been supplied. This is a suggested follow-up practice, not a replacement invoice due date or a statutory time limit imposed on the customer. Keeping that distinction explicit avoids accidental concessions in routine emails.
Administrative correction should not obscure the payment framework
The French default B2B payment period is 30 days after receipt of goods or completion of services, subject to regulated agreements and specific regimes. This official reference is not a shortcut for calculating every invoice deadline. It establishes that a legal framework exists beyond the customer’s internal purchasing workflow. Service Public Entreprendre, payment terms, verified 7 August 2026.
The French Payment Observatory also explains that missing information does not automatically justify late settlement when the invoice identifies the debt. Its guide recommends agreeing invoicing requirements early. Together, these points support cooperation with a correction without silently restarting the payment clock. Observatory guide, November 2024, pages 6 and 13.
If the customer asks for a new issue date solely to restart its internal deadline, refer the request to the person responsible for invoicing. The appropriate correction depends on the actual error and applicable rules. Preserve the document history. Replacing a document merely to achieve an accepted status in a portal can create a misleading record of what happened.
Worked simulation: the cost of crossing departments
A fictional SME reviews 20 invoices issued in one month. Six were rejected because a purchase order reference was missing. The observed proportion in this example is 6 / 20 = 30%. It is not a French market estimate. It is an invented internal sample used to illustrate how the business could diagnose its own process.
The six invoices total €18,000 including VAT. For each invoice, sales administration spends 12 minutes locating documents, the account manager spends 8 minutes identifying the buyer, and accounting spends 10 minutes correcting and checking the case. Total work is 6 × (12 + 8 + 10) = 180 minutes, or three hours. Assuming a single illustrative fully loaded cost of €40 per hour produces €120 of handling cost.
The calculation does not include financing costs or an assumed lost sale. It also does not prove that a process change will automatically release three hours. To test an improvement, the business measures the same activities on subsequent invoices and checks whether the reference is now obtained before issue. Fewer rejections in comparable cases would provide useful evidence of progress.
Remove the block rather than merely closing the ticket
Obtaining a number is only one step. Check that it belongs to the invoice, that an authorised colleague handles any document correction and that the customer’s accounting team confirms processing. Ask whether another approval remains outstanding. An invoice may move from “missing order” to “delivery awaiting confirmation” without reaching a planned payment.
Record the date the order was received, the date the block was removed and any promised payment date separately. Otherwise, an administratively corrected case may be presented as collected cash. If the customer instead confirms that it already paid, switch to investigating an unallocated payment rather than continuing to chase purchasing.
Make the handover visible to the colleague who will send the next reminder. They should know what was missing, what has now been supplied and which question remains unanswered. A concise case note with the relevant attachment is enough. Reconstructing the same story from several inboxes adds work without improving the customer’s experience.
Prevent the next blocked invoice
At the beginning of the relationship, establish whether an order is required, who supplies it, when it becomes available, which company it covers and where the invoice goes. For recurring services, also check the covered period and authorised amount. A reference that works in January may be exhausted or closed later in the year.
The guide to preventive debt collection places that preparation within the commercial relationship. Invoice tracking then makes individual blocks visible. When evaluating debt collection software, ask how a “missing purchase order” reply becomes an understandable exception for your team. Assess the action it enables, the context it preserves and the way an appropriate conversation resumes after the problem is resolved.
Sources
- Service Public Entreprendre: mandatory invoice information, verified 11 August 2026.
- Service Public Entreprendre: B2B payment terms, verified 7 August 2026.
- French Payment Observatory: good practice guide, November 2024, pages 6, 7 and 13.
