Every VAT-registered business encounters the occasional mistake, whether due to timing differences, misposted invoices or simple human error. For many years, businesses corrected these issues by submitting form VAT652. However, from 5 September 2025, HMRC withdrew this form entirely, meaning that all VAT corrections must now be made through updated processes.
Understanding how to correct errors properly is vital. Failing to follow the correct route can lead to delays, penalties or even the rejection of refund claims. This guide sets out the current rules and explains the steps to take depending on the nature of the error and its value.
Why Form VAT652 Was Withdrawn
Form VAT652 had been used for many years to disclose VAT errors. Over time, however, HMRC’s systems have moved towards digital communication, and the form no longer aligned with modern processes. Its withdrawal reflects a shift toward online submissions and the desire for clearer and more consistent reporting.
Although the withdrawal does not change the underlying VAT legislation or the types of errors that must be reported, it changes the mechanism through which corrections must be made. Businesses now have three options:
- Correct the error in the next VAT return
- Correct the error using HMRC’s online service
- Notify HMRC in writing where online submission is not possible
Knowing which route to use is essential.
1. Correcting Errors in the Next VAT Return
Many errors can be corrected simply by adjusting the figures on the next VAT return. This applies only where:
- The net value of the error is £10,000 or less, or
- The error is between £10,000 and £50,000 and does not exceed 1% of the Box 6 figure (net outputs) for the period in which the error was discovered.
The “net value” refers to the overall difference between VAT overpaid and underpaid. For example:
- If £3,000 of VAT was underdeclared, but £1,000 was overdeclared elsewhere, the net error is £2,000.
Errors can only be corrected in the next return if they were made carelessly. Deliberate errors must always be disclosed directly to HMRC.
How the Adjustment Works
The correction is entered as an adjustment in Box 1, 4 or 7 depending on the type of error. No additional forms or disclosures are required. This route is the simplest option, but only applies when the error falls within the thresholds.
2. Correcting Errors Using HMRC’s Online Service
Some errors cannot be corrected in the next return. These must be reported directly to HMRC using the online correction service. This applies when:
- The error exceeds £50,000, or
- The error is between £10,000 and £50,000 and exceeds 1% of the Box 6 figure, or
- The error was made deliberately.
Because HMRC requires detailed information for significant or deliberate errors, the online service asks for a comprehensive breakdown. Businesses must provide:
- An explanation of how each error arose
- The VAT periods affected
- Whether the error relates to input tax or output tax
- The amount underdeclared or overdeclared for each period
- How the figures were calculated
- Confirmation of whether any payments were made to HMRC that were not due
- The total amount to be corrected
HMRC stresses that refund claims will only be processed if all information is complete. Missing or unclear details may lead to delays or queries.
How to Access the Online Service
Businesses must sign into their Government Gateway account. The correction is submitted directly to HMRC, creating a digital record of the disclosure.
This method is now the primary route for notifying HMRC of significant VAT errors, replacing the previous VAT652 pathway.
Notifying HMRC in Writing
If the business cannot use the online service—for example, due to accessibility issues or system problems—HMRC will accept a written disclosure. The same set of information required for online submissions must be included in the letter.
The letter must be sent to:
BT VAT
HMRC
BX9 1WR
To avoid delays, the letter should also include:
- The VAT registration number
- Contact details for the business
- Supporting schedules where needed
Written notifications are treated in the same way as online disclosures once received, but turnaround times may be longer.
Understanding the Time Limits for Correcting Errors
VAT has strict time limits for corrections, and these depend on whether the error relates to overclaimed or underclaimed input tax or incorrect output tax.
The general rule is a four-year time limit:
- For output tax errors or over-claimed input tax, the business has four years from the end of the accounting period in which the error was made.
- For under-claimed input tax, the business has four years from the due date of the VAT return for that period.
Deliberate errors are not protected by the four-year limit. HMRC can go back further where dishonesty is involved.
What Counts as an “Error”?
The rules apply to genuine mistakes, not routine adjustments. Examples of errors include:
- Misposting VAT on sales or purchases
- Incorrect treatment of zero-rated or exempt supplies
- Mathematical miscalculations
- Accidental omissions of invoices
- Use of an incorrect VAT rate
Deliberate understatement, by contrast, is not an error: it is a compliance failure and must be disclosed using the direct notification routes.
Common Scenarios and How to Handle Them
Overclaimed Input Tax
If your business accidentally reclaimed VAT on an item that is not recoverable, such as client entertaining or a non-business purchase, the correction must follow the thresholds above.
Underdeclared Output Tax
This arises when sales VAT has been recorded incorrectly or omitted. If the error is discovered and corrected within the permitted thresholds, it can be handled through the next return.
Deliberate Understatement
This must always be disclosed directly. It cannot be corrected through a future return.
Errors Spanning Multiple VAT Periods
Large, cumulative errors may exceed the 1% rule even if no single period contained a significant mistake. These must be disclosed online or in writing.
Why Accurate Information Matters
VAT corrections must be transparent and evidenced. HMRC will not accept vague disclosures. Businesses must ensure that the submitted information:
- Matches accounting records
- Reflects correct VAT calculations
- Explains the sequence of events clearly
A clear, complete submission reduces the likelihood of HMRC raising further queries.
Best Practices for Avoiding VAT Errors Going Forward
To reduce the risk of future corrections:
- Review VAT returns before submission
- Implement regular internal checks
- Keep up-to-date VAT training for key staff
- Confirm VAT rates for unusual transactions
- Reconcile input and output tax balances regularly
These steps help reduce the administrative burden and potential penalties linked to VAT errors.
This article is for general information only; seek tailored advice before acting.
