Lesson 3 of 5
Debit memos and invoice corrections
8 min
A debit memo is the mirror image of a credit memo. The customer was under-billed and owes you more. It is less common than a credit, partly because customers do not complain about being undercharged, and partly because companies are cautious about sending extra bills. But it is a legitimate, controlled way to collect what is owed.
- Debit memo requestSales document (type DR in the standard system), usually with reference to the original invoice
- ReviewBilling block or approval rule confirms the additional charge is justified
- Debit memoOrder-related billing creates the debit memo (billing type L2 in the standard system)
- Journal entryDebits the customer account and posts additional revenue and tax
- CollectionThe debit is an open item that is paid, dunned or disputed like any invoice
Typical business cases
| Case | Contoso example | Why a debit memo |
|---|---|---|
| Price too low | Invoice used last year's $190 price instead of $200 | Collect the $10 difference per unit |
| Freight or surcharge missed | Expedited freight of $350 was agreed but not billed | Charge the agreed service separately |
| Quantity under-billed | Customer received 52 alternators, invoice shows 50 | Bill the 2 missing units if no further delivery-related billing is possible |
| Contract adjustment | Annual volume shortfall penalty agreed in the contract | Bill the agreed adjustment with a clear reference |
When Contoso would use a debit memo request.
Most of these cases point to a defect upstream: a price condition that was not maintained, a freight condition missing from the pricing procedure, or a quantity that did not flow from delivery to billing. A debit memo fixes the customer's account. It does not fix the cause. Every debit memo should prompt the question "why did billing get this wrong?"
Invoice correction requests
When one invoice has several errors, some too high and some too low, creating separate credit and debit memo requests is clumsy. The invoice correction request (type RK in the standard system) is created with reference to the invoice and copies each item twice: once as a credit for the original value and once as a debit for the corrected value. You correct the debit lines; the net difference becomes a credit or debit to the customer. The original invoice stays untouched, and the correction is fully traceable to it.
| Item on invoice 90001877 | Credit line (original) | Debit line (corrected) | Net effect |
|---|---|---|---|
| CMC-ALT-100, 50 pcs | 50 × $210 = $10,500 credit | 50 × $200 = $10,000 debit | $500 credit |
| Expedited freight | $0 credit | $350 debit | $350 debit |
| Invoice total | $10,500 credit | $10,350 debit | $150 net credit to the customer |
Debit memo versus a new invoice
Why not just raise a new standard invoice for the difference? Because a debit memo request referenced to the original invoice tells the full story: what was billed, what should have been billed, and why. A free-standing invoice for "$350" leaves the customer and your collections team guessing. Reference documents and order reasons are what make the correction auditable.
- Did goods physically come back?Yes → return order · No → continue
- Is only one direction of correction needed?Yes, customer over-billed → credit memo request; customer under-billed → debit memo request · No → continue
- Are there mixed corrections on one invoice?Yes → invoice correction request · No → continue
- Should the invoice never have existed?Yes → cancel the billing document · No → ask the process owner which correction applies
What would you do?
Contoso's sales team discovers that 120 invoices last quarter used last year's price for CMC-ALT-100. The process owner wants to collect the difference. Luis, the cutover manager, points out the price condition was migrated with the wrong validity dates. What is the most complete response?
- A debit memo request collects an under-billed amount; it is billed as a debit memo.
- Typical cases: price too low, missed freight or surcharge, quantity under-billed, contract adjustments.
- An invoice correction request nets several corrections against one invoice in a single document.
- Always reference the original invoice and set a clear order reason so the correction is auditable.
- Every correction should trigger a root-cause question about master data or configuration.
Check your understanding · not graded
Lesson check
1. What does a debit memo do to the customer account?
2. Which document handles several too-high and too-low items on one invoice?
3. Why reference the original invoice on a debit memo request?
4. A price condition was migrated with wrong validity dates. What should happen besides issuing debit memos?