Answers · UK 2025/26
How do I appeal an HMRC penalty?
You normally have 30 days from the date on the penalty notice to appeal. You can appeal online or in writing (often using form SA370 for Self Assessment), explaining your 'reasonable excuse'. If HMRC rejects it you can request a statutory review or take the case to an independent tax tribunal. Pay or appeal promptly to limit interest.
Full answer
HMRC issues penalties for things like filing a tax return late, paying tax late, or errors in a return. You can challenge most penalties if you have a valid reason. The deadline to appeal is usually 30 days from the date shown on the penalty notice. For Self Assessment late-filing or late-payment penalties you can appeal online through your HMRC account, or by post using form SA370. Other taxes have their own routes, and the notice itself tells you how to appeal. To succeed you generally need a 'reasonable excuse' -- something that stopped you meeting an obligation despite taking reasonable care. HMRC accepts examples such as a serious illness, a bereavement close to the deadline, a fire or flood, prolonged service problems with HMRC's online systems, or unexpected hospital stays. Excuses HMRC normally rejects include not having the money to pay, finding the system too difficult, or relying on someone else who let you down. Once the excuse ends, you must put things right without unreasonable delay. If HMRC rejects your appeal, you have two further options: ask for a statutory review (an independent HMRC officer reconsiders the case, free of charge) or appeal to the First-tier Tribunal (Tax), which is independent of HMRC. You can do the review first and still go to tribunal afterwards if you remain unhappy. Important on payment: appealing the penalty does not pause interest on unpaid tax, and late-payment penalties can grow. Where you can, pay the disputed amount or set up a Time to Pay arrangement to stop further charges, and you will be refunded if your appeal wins. Worked example: a GBP 100 fixed late-filing penalty for a missed Self Assessment deadline can be cancelled if you show a reasonable excuse, but if your return stays outstanding, daily penalties and further fixed charges can be added, so act quickly. Use a self-employed tax calculator to confirm what you actually owe before appealing, and check the exact penalty amounts and deadlines on gov.uk.
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This answer is informational only and does not constitute financial, tax or legal advice. Figures are for the 2025/26 UK tax year. See our methodology and sources.