A debit memo is a document that increases what one party owes another, issued after the original invoice rather than instead of it. Debit memorandum is the full form of the same term, and debit note is the same document under another name. The sender does not touch the original invoice, which keeps its number and its amount, so the memo stands as a separate document carrying its own number, its own date and its own amount.
The name covers two different documents.
A Debit Memo Between Trading Partners
The first sense is commercial. Something was billed short, and a memo raises the balance on an account that already has an invoice against it. Washington State’s statewide accounting glossary defines it in both directions, calling a debit memo a customer invoice adjustment that increases the amount due, and a debit memo for suppliers a supplier invoice adjustment that increases the amount owed (Washington State Office of Financial Management, Statewide Accounting glossary).
Either side can issue one. A seller sends one when the invoice missed freight, overtime or an agreed extra. A buyer sends one to a supplier to claim an amount back on a short shipment or on damaged goods, which is why the same document also travels as a debit note.
A Debit Memo From a Bank
The second sense is not a trading document at all. The bank is the one issuing it, and it is telling the accountholder that money has already left the account. Vermont’s state procedure describes that arrangement directly: a debit or credit memo is received by the Treasurer’s Office from the bank each time an adjustment is made to the State’s bank accounts, and usually those adjustments are the result of an incorrect deposit or a returned check (Vermont Department of Finance and Management, Debit/Credit Memo Procedure, revised 5/16/2024).
So it is the bank’s entry rather than yours, which is why it reaches the books late and gets sorted at the cutoff in bank reconciliation, and which side of an account the debit falls on is set out in debit vs credit. Where the charge is a returned item, the memo is the notification and the rules that let the bank take the money back sit in NSF check.
What the Document Has to Carry
Beyond its own number, date and amount, a debit memo has to name the document it is issued against. Vermont’s procedure has the correcting journal describe the memo by its number and its date and requires the same reference number on every entry that processes it (Vermont Department of Finance and Management, Debit/Credit Memo Procedure, revised 5/16/2024). That trail is what lets a reviewer walk from the memo back to the invoice or the deposit behind it.
Say an invoice went out for less than the agreed price and the seller billed the difference rather than reissuing it. On the stated amounts below, the account moves like this.
stated inputs
original invoice, left unchanged 4,200
debit memo for the amount left off 450
balance owed on the account 4,650Both documents stay in the file with their own numbers, so a reviewer can see what was billed first and what was added later.
Where the Two Entries Land
The issuer raises its accounts receivable against that counterparty, and the recipient raises accounts payable against the same counterparty by the same amount. Neither side rewrites the invoice, so the balance is the two documents read together.
A bank debit memo has no counterparty to mirror it, so cash goes down and the offsetting charge belongs in an account of its own. Miami-Dade County’s job aid enters the deposit amount as a negative, identified by the bank date, and where the returned item was against an invoice payment it reinstates the invoice by creating a receivable item as a debit memo (Miami-Dade County, INFORMS job aid, Insufficient Funds (NSF) and Bank Debit Memo).
What a Debit Memo Is Not
A Credit Memo
A credit memo moves the balance the other way, reducing what the buyer owes on an invoice already sent, and it is worked through in credit memo.
A Memo Debit
A memo debit is a different thing again, a temporary hold placed on a bank account before an item settles. Regulation E’s official interpretation separates the two for check authorization services, where debiting of the consumer’s account occurs when the check or draft is presented for payment, and such a service stays exempt from coverage even when a temporary hold on the account is memo-posted electronically at the time of authorization (Consumer Financial Protection Bureau, Regulation E, official interpretation of 12 CFR 1005.3(c)(2)). A hold is a pending amount, and a debit memo reports a charge already made.
Common Questions
Because someone is telling you that you owe more than the last document said. From a supplier it usually means the invoice was short, so freight, overtime or an agreed extra is being billed against the same account. From a bank it usually means the money is already gone, most often for a fee or for an item that came back unpaid. Only one of the two has a counterparty to take it up with.
A seller, a buyer, or a bank. The direction is the same in all three cases: the sender is telling the recipient that the balance owed has gone up.
Not by itself. On a bank statement the memo is notice that the balance has already been reduced, so the withdrawal happened first and the memo reports it. Between trading partners nothing moves when one is issued, because the memo only raises a balance owed.
Accountably places trained offshore accountants inside US CPA and EA firms, and a firm can put a block of its own billing and reconciliation work through a trial task so its own reviewer sees how these memos get documented first.
