When a client disputes one line on an invoice, find out exactly what they're querying, ask them to pay the rest within your normal terms, and sort out the disputed line separately. If the line was wrong, a credit note or revised invoice corrects it without reopening everything else.
In this article
The short version
- Get the query in writing and find out exactly which line is disputed.
- Give the query one owner who knows the work.
- Ask for the undisputed amount within your normal terms.
- Correct a wrong line with a credit note or revised invoice.
- Itemise charges and put one-off work on its own invoice.
Find out exactly what's disputed and who owns it
Start by getting the query in writing. You want to know which line the client is questioning, what they think is wrong with it, and what they'd expect to see instead. A vague "we can't approve this" often turns out to be about one charge, and it's much easier to resolve once you know which.
Then check your side before you defend the figure. Look for a wrong quantity, a rate that doesn't match what was agreed, or work described too loosely for the client to recognise it. Invoicing errors are a common cause of delay, and government research found that around three in ten businesses that paid suppliers late put it down to disputed invoices.
Give the query one owner on your side, ideally whoever knows the work and can agree a correction. Without one, a disputed line tends to sit in someone's inbox while the whole invoice ages. In Adfin's aged debtors view you can assign the debtor an owner, add an action for the query, and change how that customer is chased while it's being sorted.
Ask for the undisputed amount within terms
One disputed line doesn't have to stop the rest of the invoice being paid. Work out the undisputed amount and ask the client to pay that within your normal terms while you look into the remaining line.
The Fair Payment Code, run by the Small Business Commissioner, asks the businesses that sign up to it to pay undisputed portions of invoices within terms and to resolve the disputed part within the agreed timeframe. It's voluntary, but it gives you a reasonable, recognised standard to refer to when you ask.
On a £2,307 invoice, it might look like this.
| Line | Amount | Status |
|---|---|---|
| Monthly support fee | £1,380 | Agreed |
| Equipment | £435 | Agreed |
| Extra hours, 6 at £82 | £492 | Disputed |
You ask for £1,815 within terms. Checking the timesheets, you find two of the six hours were covered by the monthly fee, so you credit £164. The client then pays the remaining £328, and you've collected £2,143 in total.
If your clients pay through Adfin, they can make a part payment against the invoice, so the agreed £1,815 can come in straight away and the balance can follow once the line is settled.
Correct the line with a credit note or revised invoice
If the line was wrong, correct it formally. A credit note amends or corrects an invoice you've already issued, so it reduces what's owed without cancelling the parts nobody disputes. Some businesses issue a revised invoice instead. Which one suits your records is worth agreeing with your accountant once, so every correction is handled the same way.
If the line was right, say so plainly and show the evidence, such as the timesheet, the signed quote or the email agreeing the extra work. Keep the reply to that one line so the conversation doesn't widen into the whole invoice.
Once it's settled, a statement gives the client a single, clear view of what's still outstanding across their account.
Set up invoices so one query can't hold up the rest
The way an invoice is laid out affects how easily a client can approve it. Describe each charge clearly, with quantities, rates and costs, and list separate tasks separately so the client can see what each amount is for. Agree payment terms before the work starts and confirm scope changes by email.
It also helps to keep one-off work off the invoice for recurring fees. If project work or extra hours go on their own invoice, a query about them is less likely to hold up the monthly fee your client has already agreed to pay.
Adfin's collection agents chase within rules you approve, and you can change those rules for a customer while their query is open.
Common questions
Should a client pay the rest of an invoice while one line is disputed? The Fair Payment Code treats paying the undisputed part within terms as good practice, though the code is voluntary. Asking clearly, with the undisputed figure already worked out, makes it easier for the client to agree.
Should I use a credit note or a revised invoice? A credit note corrects an invoice that has already been issued and reduces what's owed. Agree with your accountant which approach your records need, then use it every time.
Should I keep chasing an invoice while one line is disputed? Repeated reminders about a figure the client is querying are unlikely to help. It usually works better to change the chasing on that customer and keep asking for the undisputed amount.
How common are invoice disputes as a cause of late payment? Government research found that around three in ten businesses that paid suppliers late put it down to disputed invoices. Administrative errors were cited slightly more often.
How do I stop one query holding up a whole invoice? Itemise every charge with quantities and rates, and put one-off work on its own invoice. A query about one line or one project then leaves the rest free to be paid.
Who should deal with a disputed line on an invoice? Someone who knows the work and can agree a correction. Giving the query a named owner and a next step helps stop it sitting unanswered while the invoice gets older.
Sources
- Small Business Commissioner - Code Criteria, The Fair Payment Code (accurate as of October 2026) https://www.smallbusinesscommissioner.gov.uk/fpc/code-criteria/
- Small Business Commissioner - A Guide for Effective Invoicing (accurate as of October 2026) https://www.smallbusinesscommissioner.gov.uk/help-and-guidance/all-advice/a-guide-for-effective-invoicing/
- HMRC - VATREC13010, What is the purpose of a credit and debit note? (accurate as of October 2026) https://www.gov.uk/hmrc-internal-manuals/vat-trader-records/vatrec13010
- Department for Business and Trade - Late payments research: understanding variations in payment performance and practices (accurate as of October 2026) https://www.gov.uk/government/publications/late-payments-research-performance-and-practices-across-business/late-payments-research-understanding-variations-in-payment-performance-and-practices-across-business-sectors-and-sizes-html-executive-summary
