Tax Disputes

How to Dispute a Tax Decision from HMRC

HMRC says you owe tax. You think they're wrong. You have rights. Learn how to appeal, request a review, and escalate to the tax tribunal if needed. It's your money—fight for it.

Quick Answer

If you disagree with an HMRC tax decision, you have a right to appeal under the Taxes Management Act 1970. First, ask for an explanation. Then request a formal review (free, independent). If still unhappy, appeal to the First-tier Tribunal. You have 30 days from the decision letter to appeal, but you can request late appeal if you have a good reason.

Get Help Now

How to Appeal an HMRC Tax Decision

Request a Detailed Explanation

Write to HMRC asking them to explain the decision in detail—what law they're relying on, which facts they're disputing, and how they calculated the amount. They must respond within 30 days under the Taxpayer's Charter.

Request a Formal Review

If you disagree, ask HMRC for a formal review. This is free, takes 30–45 days, and is handled by someone independent of the original decision. Submit your evidence and arguments clearly. Reviews are often successful.

Appeal to the Tax Tribunal

If the review upholds the decision, appeal to the First-tier Tribunal within 30 days. You don't need a solicitor. The tribunal is independent and will make a fair judgment based on the evidence and the law.

What the Law Says

Legislation

Taxes Management Act 1970

Gives you the right to appeal any tax assessment within 30 days of the decision letter. You can appeal on the grounds that HMRC made an error in law, in fact, or in calculation.

Charter

Taxpayer's Charter

Sets out your rights when dealing with HMRC. You have the right to: clear explanations, timely decisions, a review if you disagree, and proper consideration of your evidence.

Procedure

HMRC Complaints Procedure

HMRC must respond to complaints within 2 months. If you're unhappy with how they've handled your case (not just the decision), you can file a complaint under the HMRC Complaints Charter.

Appeals

First-tier Tribunal (Tax)

An independent tribunal hears tax appeals. You can appeal without a solicitor. The tribunal can overturn HMRC's decision if they find HMRC made an error in law or fact.

Common Tax Dispute Scenarios

📊

Income Calculation Error

HMRC has calculated your tax based on the wrong income figure. You've provided evidence of your actual earnings. Request a review with the correct figures and your supporting documents (payslips, accounts).

🏠

Allowances Not Applied

HMRC says you're not eligible for an allowance (personal allowance, trading allowance, pension relief). Show your evidence of entitlement and request a review. Many mistakes happen here.

💼

Self-Employment Dispute

HMRC disagrees with your claimed expenses or turnover. Send detailed records: invoices, receipts, bank statements. If they still dispute it, ask for a review and provide context for how you calculated figures.

🤝

Relationship Breakdown & Tax

After a separation, HMRC assigned you jointly-held assets. You can appeal and argue that you should be assessed separately on your share only. Request a review with divorce papers as evidence.

🏦

Underpayment from Previous Years

HMRC says you owe tax from years ago and wants to recover it. You can challenge how far back they can go (usually 4 years, 6 if there's careless understatement). Request a review of the limitation period.

⏰

Missed Deadline for Claims

You have legitimate relief to claim but missed the deadline. HMRC can grant a late claim if you have a good reason. Request one in writing with your explanation.

Frequently Asked Questions

How long do I have to appeal? +

You have 30 days from the date of the decision letter to appeal. If you miss this, you can request a late appeal if you have a reasonable reason (e.g. serious illness, being abroad). HMRC must consider your reason fairly. Don't panic if you're slightly late—submit your late appeal request with a good explanation.

Do I need a solicitor or accountant to appeal? +

No. You can appeal yourself. A formal review with HMRC can be done by you in writing. If you go to the First-tier Tribunal, you can represent yourself (most people do). However, if the amount is very large or the law is complex, a tax accountant or solicitor can help.

What is a formal review? +

A formal review is a free, independent reconsideration of HMRC's decision by a different officer. You can request one if you disagree with their original decision. It usually takes 30–45 days. You submit your evidence and arguments. If the review upholds the decision, you can then appeal to the tribunal.

Can I appeal if I've missed the 30-day deadline? +

You can request a late appeal if you have a reasonable excuse (illness, bereavement, being abroad, etc.). Submit your late appeal request in writing with your excuse. HMRC must consider it fairly. Don't assume you're too late—always submit late appeals if you have a good reason.

What happens if I lose at the tribunal? You can appeal the tribunal's decision to the Upper Tribunal (a higher court) if you can show the tribunal made a legal error (not just that you disagree with the outcome). This is more specialist and usually requires a tax lawyer. However, the tribunal's decision will stand unless you can prove a legal error.

Will I have to pay the tax while I appeal? +

Usually yes, but you can request to suspend payment while you appeal. Submit a "suspension of payment" request with your appeal. HMRC may agree if you can show financial hardship or if the appeal outcome is genuinely uncertain. If you don't request suspension, you'll need to pay while the appeal is ongoing.

Ready to Appeal Your Tax Decision?

Use FightingBack's Tax tool to draft your appeal letter, request a formal review, or prepare your tribunal submission. Get professional guidance backed by UK tax law.

Start Your Tax Appeal