What Is a Credit Note? When and How to Issue One
A credit note reduces or cancels an invoice you already sent. Learn when you need one, what it must contain, and how it differs from a refund or a debit note.
The short definition
A credit note (sometimes called a credit memo) is a document a seller issues to a buyer to reduce, partly or fully, the amount of an invoice that has already been issued. It is the correct, auditable way to fix an invoice after it has been sent, instead of editing or deleting the original.
Think of it as a negative invoice: it has its own number and date, refers back to the original invoice, and shows the amount being credited, including any tax.
When you need a credit note
- Pricing or quantity errors: you charged for 10 hours instead of 8, or used the wrong rate.
- Returned goods: the customer sent back part or all of an order.
- Cancelled services: a booked service will not be delivered.
- Agreed discounts after invoicing: a goodwill discount, a volume rebate, or compensation for a problem.
- Wrong customer details: you billed the wrong legal entity and must cancel the invoice and re-issue it correctly.
- Duplicate invoices: the same work was invoiced twice.
Why not just edit the invoice?
Once an invoice has been sent, it exists in your client's records and probably in their accounting system. If you change it and re-send it with the same number, the two versions no longer match. Your sales records, tax reports and the client's books will disagree. In many tax systems, issued invoices must not be altered; a credit note is the expected correction method.
A credit note keeps a clean trail: original invoice, credit note, and (if needed) a new correct invoice, each with its own number and date.
What a credit note should contain
- The words "Credit Note" clearly at the top
- A unique credit note number (often with its own prefix, e.g.
CN-2026-0003) - Date of issue
- Your business details and the customer's details, matching the original invoice
- The number and date of the original invoice being credited
- A description of what is being credited and why
- The amount credited, with tax shown separately if the original invoice included tax
- The total credit
Where you are registered for VAT, GST or sales tax, the credit note normally also needs the tax details required by your jurisdiction so both parties can adjust their tax records. See our VAT and GST guides for background.
Worked example
You issued invoice INV-2026-0041 for 10 hours of consulting at 100 per hour, plus 20% tax: subtotal 1,000, tax 200, total 1,200. The client points out that only 8 hours were worked.
| Credit note CN-2026-0003 | Amount |
|---|---|
| Credit for 2 hours consulting over-billed on INV-2026-0041 | 200.00 |
| Tax at 20% | 40.00 |
| Total credit | 240.00 |
The client now owes 1,200 − 240 = 960. If they had already paid 1,200, you either refund 240 or keep it as a credit on their account for the next invoice. Say which in the credit note.
Credit note vs refund vs debit note
| Document / action | What it does |
|---|---|
| Credit note | Reduces the amount owed on an invoice (a document) |
| Refund | Returns money that was already paid (a payment) |
| Debit note | Increases the amount owed, or is issued by a buyer to request a credit |
A refund often follows a credit note, but not always: the credit can instead be applied to future invoices.
Full cancellation
If an invoice should never have been issued (for example you billed the wrong company), issue a credit note for the full amount, then create a fresh invoice with a new number for the correct entity. Do not delete or reuse the original number; see invoice numbering for why.
Best practices
- Issue the credit note promptly, as soon as the correction is agreed.
- Explain the reason in one clear sentence.
- Send it to the same accounts-payable contact as the original invoice.
- Keep credit notes with your invoices for the same retention period.
- Use a separate number series so credit notes are never confused with invoices.
Many credit notes are avoidable. Our list of common invoice mistakes covers the errors that most often cause them, and the invoice generator checks your totals automatically.
Frequently asked questions
Can I issue a credit note after the client has already paid the invoice?
Yes. A credit note can be issued whether the original invoice is unpaid, partly paid or fully paid. If the client has already paid, the credit note should say whether you will refund the difference or keep it as a credit on their account. Some tax authorities only let you reduce the tax you owe once a refund has actually been made, so check your local VAT or GST rules before adjusting a return.
Is there a time limit for issuing a credit note?
There is no single worldwide deadline, but tax rules often set one. In India, for example, GST credit notes for a financial year generally have to be declared by 30 November of the following year, and other countries have their own periods for correcting tax. Even where no deadline applies, issue the credit note as soon as the correction is agreed so both sets of books match. Check your tax authority's guidance for the exact rule.
Can I reuse the original invoice number with a suffix, like INV-0041-A, for the credit note?
It is better not to. A suffix makes the credit note look like a revised version of the invoice, which is exactly what you are trying to avoid. Give the credit note its own unique number from a dedicated series, such as CN-2026-0003, and quote the original invoice number in the body. That way each document stays traceable and your invoice sequence has no gaps or look-alike numbers.
How do I record a credit note in my accounting records?
As the seller, you record a credit note as a reduction of sales and of the amount the customer owes you, plus a reduction of the tax you collected if tax was charged. The buyer does the reverse: it reduces its purchases, the amount it owes you and any input tax it planned to reclaim. Most accounting software has a dedicated credit note feature that posts these entries and links them to the original invoice.
Can the buyer issue the credit note instead of the seller?
Normally no. The seller issues the credit note because it corrects the seller's own invoice. A buyer who wants a reduction usually sends a debit note or a written request explaining what should be credited and why. The exception is a formal self-billing arrangement, where the buyer creates invoices and credit notes on the seller's behalf under an agreement that some tax authorities require to be documented in advance.
Can I apply a credit note to a different invoice from the one it corrects?
Yes, if the client agrees. A credit note always references the invoice it corrects, but the resulting credit can be offset against another open invoice or a future one instead of being refunded. Write down which invoice the credit is being applied to, for example in the notes of the next invoice or on a statement of account, so both sides can reconcile the balance without confusion.
Should the amounts on a credit note be shown as negative numbers?
Either approach is acceptable as long as the document is clearly titled Credit Note. Many businesses show positive amounts under a Credit Note heading, because the title already tells the reader the figures reduce what is owed. Others show negative amounts so totals can be added straight into a ledger. Pick one style and use it consistently so your client's accounts team never has to guess.
Does a credit balance on a customer's account expire?
There is no universal expiry rule for a credit note balance between businesses. Unless your terms say otherwise, the credit remains owed to the customer until it is used against a future invoice or refunded. If you want credits to lapse or be refunded after a set period, state that in your terms and on the credit note. Consumer protection laws in some countries limit how credits can expire, so check locally.
Do I still need a credit note if I am not registered for VAT or GST?
Yes, it is still good practice. Even without tax registration, a credit note keeps your sales records, numbering and client balances accurate, and it gives your client a document to file against the original invoice. Simply leave out the tax lines and registration number. If you later register for tax, your clean correction history will make the transition and any review of past records much easier.
When can I void an invoice instead of issuing a credit note?
Voiding is generally only appropriate when the invoice has not yet been sent to the client or recorded anywhere outside your own system. In that case, mark it void, keep the number in your records with a short reason, and move on. Once an invoice has reached the client, it may already be in their accounts, so a credit note is the safer, auditable way to cancel or reduce it.
Invoice Creator Editorial Team
Guides on invoicing, cash flow and small-business finance from Invoice Creator, operated by Next Software Development Company. Content is reviewed for accuracy against the fields our own invoice generator produces.
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