VAT Bad Debt Relief Explained: How to Reclaim VAT on Unpaid Invoices

VAT bad debt relief lets an eligible VAT-registered business reclaim the output VAT it has already accounted for and paid to HMRC on a sale for which its customer has not paid. The debt generally must remain unpaid six months after the later of the payment due date and the supply date; the business must write it off in its VAT records and meet HMRC’s conditions. This is not an automatic refund simply because an invoice becomes overdue.

If your business has paid £400 VAT on a £2,400 invoice and the entire amount remains unpaid, the potential relief is £400, provided the full claim conditions are met. If the customer has paid part of the bill, the relief is limited to the VAT in the unpaid balance. This guide explains the clock, the calculations, the bookkeeping evidence and exactly what happens when money arrives later.

Quick answer: can your business reclaim VAT on an unpaid invoice?

For most businesses accounting for VAT on the invoice basis, the answer is potentially yes. Check all of these conditions before making an entry on a VAT Return:

• You supplied goods or services on which VAT was due, accounted for that output VAT, and paid it to HMRC.
• The customer has not paid the relevant debt, wholly or partly, after the qualifying six-month period.
• You have actually written the debt off in day-to-day VAT records and transferred it to a separate bad-debt account.
• The amount charged was not more than the customary selling price, and the debt has not been sold or absolutely assigned in a way that prevents relief.
• You are still within the four years and six months normal claim window, measured from the later of the due date and supply date.
• You can show the underlying invoices, original VAT Return, collections, partial receipts, bad-debt records and claim period.

These conditions come from HMRC VAT Notice 700/18. Specific rules apply to margin schemes, finance arrangements, factoring and VAT groups, so unusual transactions need a separate review.

VAT bad debt relief versus an ordinary overdue invoice

An invoice becomes overdue under the contract when the customer misses the agreed payment date. That does not automatically entitle you to recover its VAT. HMRC has a separate timing and evidence test, and you must also write the debt off for VAT purposes. Writing off for relief does not necessarily mean that you have stopped attempting civil recovery, nor does it cancel the customer’s obligation to pay.

A commercial credit-control decision and a tax-relief decision should work together, but they are not identical. Preserve your recovery correspondence even after recognizing the accounting write-off.

When does the six-month clock start?

HMRC measures the wait from the later of the date the supply took place and the date payment became due and payable. It is not always six months after you sent the invoice. Contract changes or agreed longer credit terms can move the start date.

Example A — standard credit terms. Services are supplied on 10 January; the valid agreed invoice due date is 9 February. Six months is measured from 9 February, not 10 January. The entitlement date is determined by the later date and the actual calendar period; do not claim in a VAT period before entitlement arises.

Example B — a valid payment extension. If the parties genuinely agree before the relevant claim that a February debt is payable in April, the April due date may affect the relief date. Preserve the agreement and review its real legal and commercial effect.

Example C — late invoice. If the supply was made earlier but its payment date is later, the due date normally drives the comparison. Review the time-of-supply rules before assuming the invoice date controls everything.

The normal deadline to make a claim is four years and six months after the later of the supply date and the payment due date. That deadline is not a promise that a business can automatically claim on any later return. A missed claim, amended return and deregistration require specific consideration. See HMRC’s full relief guidance.

How much VAT can you recover? Use the correct VAT fraction

For a standard-rated invoice with VAT at 20%, the VAT contained in an unpaid VAT-inclusive sum is generally one-sixth. If the supply was at another rate, use the correct fraction and the original tax treatment. Do not multiply the VAT-inclusive debt by 20%: that would overstate the claim.

In the simple examples above, the potential claim equals outstanding gross debt ÷ 6, assuming 20% VAT, no complicating allocation, and every statutory condition is met. HMRC has special rules for allocating payments across invoices, including supplies with different VAT rates; the customer may designate a payment for a particular invoice. Do not just apply a blanket fraction to all outstanding debtors.

Worked case study: £12,000 sales invoice, £3,000 collected

A UK consultancy issues a standard-rated invoice for £10,000 plus £2,000 VAT, total £12,000. The business pays the £2,000 output VAT through its original VAT Return. The customer pays £3,000 and does not pay the remaining £9,000.

If six months have passed from the later relevant date and all relief requirements are satisfied, the business may claim £1,500 VAT (£9,000 ÷ 6). It is not entitled to recover the full £2,000 because it collected part of the invoice. Its VAT bad-debt record must show the £3,000 receipt, the write-off, which return first accounted for the £2,000, and the later return containing the £1,500 relief.

Do not confuse the £9,000 outstanding customer balance with £9,000 of tax relief. The VAT claim in this example is £1,500. The remaining underlying commercial loss has its own accounts and direct-tax treatment, which is not necessarily identical to the VAT entry.

How to claim VAT bad debt relief on your VAT Return

Once entitlement exists and your evidence is complete, HMRC says to include the VAT relief in Box 4 of the VAT Return covering the date you meet the conditions. This is input-tax side reporting for the relief; it does not authorize an unexplained adjustment to sales turnover or another box.

1. Identify the original sales invoice, VAT rate, supply date and agreed due date.
2. Reconcile all payments, credit notes, legally agreed adjustments and any third-party receipts.
3. Confirm the VAT was previously accounted for and paid, and that the six-month and claim-limit tests are met.
4. Post the formal bad-debt write-off and create the separate VAT bad-debt record.
5. Calculate the correct recoverable VAT, considering mixed rates, security and special rules.
6. Include the claim in Box 4 of the eligible VAT Return, with a clear audit trail in your MTD-compatible software.
7. Review later receipts on the account and reverse the relevant VAT relief if any recovery occurs.

For an MTD VAT business, the correct digital bookkeeping trail matters: a manual worksheet on its own should not break required digital records or links. See Britvex’s VAT Registration & Returns services for VAT-return preparation and review.

Why you need a separate VAT bad-debt account

HMRC expects records beyond the ordinary aged-debtors list. Your file should be capable of showing what HMRC would ask for in a review, including the amounts originally taxed, the period of original accounting, the claim period, and later repayments. A practical record contains:

HMRC’s special relief-record requirement is generally four years from the claim, but this does not replace the ordinary six-year VAT record-retention rule where it applies. Keep records for the applicable longer period, and follow any preservation requirement for an ongoing enquiry. HMRC VAT Notice 700/18, section 2.5–2.8 gives the detailed requirements.

What happens if the customer pays after you claim?

A VAT bad-debt claim does not mean you keep the VAT permanently if payment later arrives. HMRC requires you to repay the VAT element in the recovery, normally by entering that amount in Box 1 of the VAT Return for the payment period.

Return to our £12,000 case study. The business had claimed £1,500 on £9,000 outstanding. Three months later it recovers £3,600. At 20% VAT, that recovery contains £600 of VAT (£3,600 ÷ 6). The business adds £600 to Box 1 and records the payment in the VAT bad-debt ledger. The remaining relief needs a further reversal if and when more money is received.

If the business has deregistered for VAT by the time recovery occurs, it must not ignore the repayment obligation. HMRC says to contact it for the appropriate route. A professional review can prevent errors when a company changes status or transfers its business.

Cash Accounting Scheme, Flat Rate Scheme and other exceptions

Cash Accounting Scheme. Under ordinary VAT cash accounting, a business generally pays output VAT on customer receipts rather than issuing invoices. Consequently, a separately unpaid customer debt has not generated the same VAT payment, so the standard bad-debt relief mechanism is usually unnecessary. Check exceptions and any transition between schemes.

Flat Rate Scheme. Flat Rate VAT accounting can create different calculations and entitlement conditions, particularly on leaving or combining schemes. Do not assume the standard invoice-based example applies unchanged. Check the specific HMRC scheme rules and the amounts actually accounted for.

Annual Accounting Scheme. HMRC acknowledges that an eligible debt may qualify for relief on the same annual VAT Return in which output tax was originally accounted for, if six months have passed and conditions are met by the end of the period.

Margin schemes. Relief is usually constrained by the VAT actually accounted for on the margin; an unpaid gross invoice does not create a refund beyond that amount.

Factored or assigned invoices. An outright legal assignment of the debt can block relief. Arrangements allowing reassignment need careful contractual examination, not just an assumption that the customer owes someone money.

Insured debts, guarantors and security. Insurance and third-party payments are not always treated alike. Payments from a guarantor can reduce entitlement, and an enforceable security may reduce the amount on which relief is based. Refer such cases for individualized analysis.

You cannot issue a credit note just because a customer has not paid

One of the most expensive bookkeeping mistakes is treating a genuine unpaid debt as though the sale never happened. HMRC says a VAT credit note cannot simply be issued for non-payment. It is appropriate only where there is a genuine commercial price reduction, error or other valid adjustment. An unpaid invoice and a corrected invoice are not interchangeable.

Similarly, do not reduce sales figures on a later VAT Return without a valid underlying mechanism. Use the bad-debt relief route, correctly supported by invoices, ledger entries and timing, where that is the actual situation.

Unpaid supplier bills: the reverse-side rule many businesses miss

Bad-debt relief is not just about customers who do not pay you. A VAT-registered business that has recovered input VAT on a purchase but has not paid its supplier within six months of the relevant date may be required to repay the proportion of that input VAT, even if the supplier never asks for repayment.

Example. Your business reclaims £200 input VAT on a £1,200 standard-rated purchase. It pays only £500 and leaves £700 outstanding beyond the relevant date. Subject to the normal rules, the input VAT clawback would be £116.67 (£200 × £700/£1,200). The business reduces its Box 4 input tax claim accordingly. If it later pays the supplier, the relevant input tax can generally be reclaimed then. This obligation is often missed when accounts payable and VAT are handled separately.

See HMRC Notice 700/18, section 4 for the supplier-side requirements and exceptions.

Common mistakes to avoid before you submit

• Using the invoice date without checking the actual supply and agreed due dates.
• Claiming relief on a debt that has not been formally written off in VAT records.
• Reclaiming VAT that was not previously accounted for and paid.
• Calculating 20% of the gross unpaid invoice, rather than the VAT fraction.
• Ignoring deposits, part payments, allocations, credit notes and guarantor payments.
• Treating a sold or factored receivable as automatically eligible.
• Making a claim outside the four-year-six-month normal limit.
• Failing to account in Box 1 for money received after claiming.
• Forgetting to reverse input VAT on old unpaid supplier invoices.

VAT credit-control checklist: reconcile debtors monthly; flag later-of-due-date six-month eligibility; document commercially genuine write-offs; preserve source VAT Returns; check claims before sign-off; and review recoveries each quarter. This is a repeatable process, not a one-off year-end adjustment.

How Britvex can help with unpaid invoices and VAT returns

Britvex can help reconcile debtor ledgers, review VAT bad-debt eligibility, calculate claims, prepare the proper supporting schedule and check the entries in an eligible VAT Return, subject to an agreed engagement. We can also help review whether the business’s chosen VAT scheme is suitable for its cash-collection pattern.

Start with a concise brief: your VAT period, accounting scheme, invoice dates, due dates, VAT originally paid, customer receipts and copies of collection correspondence. For new enquiries contact info@britvex.co.uk or +44 20 3758 7500. Existing clients can use the secure portal or support page. For broader VAT assistance, see Britvex VAT services.

Frequently asked questions

Official HMRC and UK government references

• HMRC VAT Notice 700/18: Relief from VAT on bad debts
• GOV.UK: Keeping VAT records
• GOV.UK: What to include in a VAT Return

About Britvex: BRITVEX ADVISORY LTD (company number 16133503) is an England and Wales company and an approved Companies House Authorised Corporate Service Provider (ACSP). Britvex is supervised by HMRC for anti-money laundering purposes and registered with the ICO. The company was founded by Syed Raheel Shahzad and is part of The Syed Group. Information is general UK guidance, not advice on a specific transaction, and regulatory rules may change. Read together with the official sources above.