What is a debit memo?
Quick answer
A debit memo is a document that records an adjustment outside the normal invoice. A seller sends one to bill a customer for an amount left off an invoice, such as an undercharge or extra freight. A buyer may send one to a vendor to record a return or shortage it is deducting. Banks also issue them for fees.
Last updated
Updated · By Robert Breen
Why it matters for a small business
Small billing corrections need a paper trail. If an invoice went out $60 too low, reissuing it confuses everyone who already saw the first version. A debit memo that names the original invoice number and the reason bills the difference cleanly, and your accounts receivable report shows both documents side by side.
On the buying side, some accounts payable teams issue a debit memo when goods arrive damaged or short, then pay the invoice minus that amount. That only works smoothly when the vendor agrees, because until the vendor issues a matching credit memo, its books still show the full balance as owed. A bank debit memo is different again: it is a fee or charge on your statement, and it turns up when you reconcile the account.
In a real lesson: Build an AI Vendor Follow-Up Agent in n8n
Stepthrough has no lesson that writes debit memos. The closest is the AI Vendor Follow-Up Agent lesson, built for Ridgeline Supply Co., a made-up warehouse and distribution business. One of the orders you hand the agent is "Northwind Wrap, PO 4492, 12 rolls short," which is exactly the kind of problem a buyer's debit memo can settle.
The agent's system prompt tells it to name the PO number and what was ordered, state the problem in one sentence and ask one clear question: "a ship date, a tracking number, or a fix." It also says "Do not threaten to cancel orders or invent penalties."
That is the right order of events. Ask the vendor first. If the vendor agrees to a reduction, Ridgeline's AP team can record a debit memo for the 12 rolls, or wait for the vendor's credit memo, and pay the rest. The decision and the memo stay with people.
Try this lesson free or read the step-by-step guide.
Common confusions
Debit memo vs credit memo
A credit memo lowers what the customer owes. A seller's debit memo raises it. A buyer's debit memo is the buyer's own record of a reduction it is claiming, which the vendor usually answers with a credit memo.
Debit memo vs invoice
An invoice bills a sale. A debit memo adjusts a bill that already exists and should always point back to it.
Tips
- Put the original invoice or PO number and a one-line reason on every memo.
- Agree on a shortage or return with the vendor before deducting it from a payment.
- Review bank debit memos each month so unexpected fees get questioned quickly.
Related terms
More Business terms
Where you use it: free lessons
- Build an AI Vendor Follow-Up Agent in n8n (n8n, 12 min)
More free tutorials
Frequently asked questions
- Who issues a debit memo, the buyer or the seller?
- Either. A seller issues one to add a charge to a customer's account, for example after an undercharge. A buyer issues one to a vendor to record a deduction for a return or shortage. Read the reason line to know which kind you have.
- What is a debit memo on a bank statement?
- It is a charge the bank took from your account outside a normal check or card payment, such as a service fee, a returned deposit or a wire fee. Match each one during your monthly bank reconciliation.
- Is a debit memo the same as a debit note?
- Yes, in most places the two names mean the same document. Some companies and countries prefer one term over the other, but both record an adjustment that raises a balance or claims a deduction.