HMRC Penalties: A Complete UK Guide

HMRC operates a comprehensive penalty regime designed to encourage compliance and deter non-compliance. Penalties apply across all major taxes, including income tax, corporation tax, VAT, and national insurance contributions. Understanding how penalties are calculated and how to minimise them is essential for anyone dealing with HMRC.

Late Filing Penalties

Failing to file your tax return on time triggers an automatic penalty regime. For self assessment, the initial penalty is £100 immediately after the filing deadline (31 January). If the return is still outstanding after three months, daily penalties of £10 per day apply, up to a maximum of £900 (90 days). After six months, a further penalty of 5% of the tax due or £300, whichever is greater, is charged. After 12 months, another 5% or £300 penalty applies, and in serious cases, HMRC can impose penalties of up to 100% of the tax due.

The penalties accumulate quickly. A return filed 12 months late with a tax liability of £10,000 could attract penalties of over £1,500 plus interest, before the underlying tax is paid. HMRC has discretion to reduce or suspend penalties in certain circumstances, such as where the late filing was due to circumstances beyond your control.

Late Payment Penalties

Late payment penalties apply where you fail to pay the tax due by the deadline. For self assessment, the late payment penalty is 2.75% of the unpaid tax plus Bank of England base rate, calculated daily from the due date. If the tax is still unpaid after 30 days, an additional 2.75% penalty is charged. Further penalties apply if the tax remains unpaid after six and 12 months.

VAT late payment penalties operate differently. Under the default surcharge regime, a first default does not result in a penalty but triggers a surcharge period. If you default again within the period, penalties start at 2% of the tax due and rise to 15% for repeated defaults. From January 2023, HMRC introduced a new points-based penalty system for VAT, replacing the default surcharge regime.

Accuracy Penalties

If your return contains an inaccuracy that results in a loss of tax, HMRC can charge an accuracy penalty. The penalty percentage depends on the behaviour that caused the inaccuracy:

The penalty can be reduced if you make a disclosure to HMRC. An unprompted disclosure (telling HMRC about the error before they discover it) qualifies for the maximum reduction. A prompted disclosure (after HMRC has started an enquiry) qualifies for a lower reduction. The quality of the disclosure also matters — providing full details, access to records, and active assistance results in the highest reduction.

Prompted vs Unprompted Disclosure

The distinction between prompted and unprompted disclosure is critical for penalty reduction. An unprompted disclosure occurs when you tell HMRC about an inaccuracy before they have contacted you about it. In this case, the minimum penalty percentages are: 0% for careless, 20% for deliberate but not concealed, and 30% for deliberate and concealed. A prompted disclosure (after HMRC has opened an enquiry) gives minimum penalties of: 15% for careless, 35% for deliberate but not concealed, and 50% for deliberate and concealed.

Making an unprompted disclosure not only reduces penalties but may also reduce the risk of criminal prosecution for serious cases. If you discover an error in your return, disclosing it promptly is always the best course of action.

Penalty Suspension and Appeals

HMRC can suspend an accuracy penalty for up to two years if certain conditions are met. The suspension is conditional on you meeting specified requirements, such as implementing new systems or procedures to prevent future inaccuracies. If you comply with the conditions, the penalty is cancelled at the end of the suspension period.

You can appeal any penalty to HMRC within 30 days, and subsequently to the tribunal. Grounds for appeal include: having a reasonable excuse for the failure, the penalty being disproportionate, or HMRC having made a procedural error. Reasonable excuse might include serious illness, bereavement, or circumstances beyond your control — but it does not include lack of funds or reliance on an adviser without checking their work.

Browse more UK tax compliance and disputes guides or try our calculators.