Free tool
I have a VAT assessment: what now?
A general guide, not advice, based on HMRC VAT Notice 700, section 21.
Why HMRC issues VAT assessments
| Reason | What it means |
|---|---|
| You have not sent a return | HMRC estimates the VAT you owe for that period |
| Your return was incomplete or incorrect | HMRC assesses the VAT it believes is due, often after a compliance check |
| A refund was paid wrongly | HMRC can assess to recover VAT or interest paid or credited to you in error |
What to do if you receive an assessment
- For a missing return: file the return with your actual figures as soon as you can. Once it is submitted, the assessment is withdrawn and the VAT due is what your return shows.
- Do not just pay the estimate. If you keep paying assessments instead of filing, HMRC increases the amount with each one.
- For an assessment after a check: read HMRC's reasons. If you disagree, you can ask for a review or appeal, usually within 30 days of the decision letter.
- Pay what you owe once the right figure is settled, to stop interest and late payment penalties building up.
Time limits on assessments
- HMRC normally cannot assess more than 4 years after the end of the VAT period.
- In special cases, such as fraud, the limit is 20 years.
- If an assessment later turns out to be too low, HMRC can issue a further assessment within the time limits.
How to avoid VAT assessments
- File every return on time, including nil returns. A missing return is the most common reason for an assessment.
- Keep digital records that support every figure, with VAT invoices for everything you reclaim.
- Check your return before you submit: Box 3 and Box 5 adding up, the right VAT rates, nothing blocked in Box 4.
- Correct errors promptly. Net errors up to £10,000, or up to 1% of Box 6 with a £50,000 limit, can go on your next return.
Late returns also earn penalty points. See VAT penalties explained.
Never miss a return again, from £5 a month
Swift VAT Pro shows every VAT period that is due from HMRC and emails you 4 days and 3 days before each deadline.
- Connect to HMRC on HMRC's own page with your Government Gateway sign-in. We never see that password.
- See your VAT periods, due dates, amounts owed and payments, read from HMRC.
- Upload your nine box totals as a CSV. Box 3 and Box 5 are worked out and every box is checked.
- Submit and keep HMRC's receipt. Reminder emails arrive before each due date.
No card needed · From £5 a month · Plans for up to 100 businesses · Filing through HMRC's MTD service since 2019
Final thoughts
Most VAT assessments start with a missing return. File every period on time through MTD software, keep records that back up each box, and if an estimate arrives, replace it with your real return quickly.
Disclaimer: This guide gives general information, not advice. If HMRC has assessed you after a compliance check, speak to an accountant or adviser before you respond.
Frequently asked questions
Checked against HMRC VAT Notice 700 (section 21, assessments), GOV.UK guidance on disagreeing with a tax decision, and VAT Notice 700/45. November 2026.
What is a VAT assessment?
How do I get rid of a VAT central assessment?
Should I just pay the VAT assessment?
How far back can HMRC assess VAT?
Can I appeal a VAT assessment?
Never miss a return again, from £5 a month.
Swift VAT Pro files your return to HMRC from the spreadsheet you already keep. From £5 a month.
No card needed · 2,900+ VAT returns filed since 2019