Guides

Writing Your Grounds of Appeal: What To Say (And What To Avoid)

Your grounds of appeal are the most important thing you write. Here's what effective grounds look like—telling the tribunal what HMRC got wrong, why it matters, and what you want instead.

Liam Williams

Liam Williams

— 14 min read

You've decided to appeal. You've read the filing guide. You've got Form T240 open in front of you—or you're staring at the equivalent screen on the online portal.

And now you've hit the box that says "Give reasons for each decision you dispute."

Most appellants get this wrong. Some write too little—"I disagree with HMRC's decision." Others write too much—five pages of frustration with HMRC's handling of their case, without ever explaining what the actual error is.

This article explains what effective grounds of appeal look like, why they matter, and what to think about when writing yours.

Why Your Grounds Matter

Your grounds of appeal are not a formality. They are the foundation of your entire case.

They set the scope of what the tribunal can consider. If your grounds don't raise an issue, the tribunal may not examine it. They shape HMRC's response—HMRC's statement of case will respond to your grounds point by point. And they signal seriousness. Vague, one-line grounds tell the tribunal (and HMRC) that you haven't thought carefully about your case. Specific, structured grounds tell them you have.

Everything that follows in the tribunal process—HMRC's response, the evidence exchange, the hearing itself—builds on what you write here. Well-drafted grounds give the rest of your appeal a solid foundation. Vague or incomplete grounds can mean spending the rest of the process trying to catch up.

What The Rules Actually Require

The good news: the legal requirements are modest. The rules want clarity, not legal scholarship.

Rule 20(2) of the Tribunal Procedure Rules 2009 requires your notice of appeal to include two things about the substance of your case:

  • (e) "the result the appellant is seeking"
  • (f) "the grounds for making the appeal"

For direct tax appeals, section 31A(5) of the Taxes Management Act 1970 adds that the notice of appeal must "specify the grounds of appeal." The word "specify" means you need to give identifiable reasons—but nothing in the legislation prescribes a format, a length, or any degree of legal detail.

The Form T240 itself is reassuring. Section 6 says: "Clearly explain why you are appealing, giving reasons for each decision you dispute. The judge will want to hear things from your side. You can write reasons here or enclose a separate document if you need more space."

The T242 guidance says the notice should include "details of your reasons for appealing, including any facts or law that you rely upon." The word "any" is permissive—including the facts is important, but you don't have to cite legislation or case law.

And underpinning all of this, Rule 2 of the Tribunal Procedure Rules sets an overriding objective that includes "avoiding unnecessary formality and seeking flexibility in the proceedings" and "ensuring, so far as practicable, that the parties are able to participate fully." The tribunal will look at the substance of what you have written, not whether it reads like a legal document.

You do not need to be a lawyer. Clear facts in your own words are sufficient.

The Three Questions Effective Grounds Answer

Effective grounds typically answer three questions for each HMRC decision being appealed:

  1. What did HMRC decide? Identify the specific decision—the penalty, the assessment, the closure notice. Include the date, the reference number, and the amount.

  2. What is wrong with it? This is the heart of your grounds. Explain the factual error, the legal mistake, or both. Be specific: what did HMRC get wrong, and why?

  3. What do you want instead? Rule 20(2)(e) requires you to state the result you are seeking. Say it clearly: "cancel the penalty," "reduce the assessment from £X to £Y," "discharge the discovery assessment."

If your grounds answer all three questions for each decision, you have done the essential work—regardless of how formally or informally you've expressed it.

How The Burden Of Proof Shapes Your Grounds

The burden of proof determines what your grounds need to address. It varies depending on the type of appeal.

Assessment Appeals

For tax assessments—including income tax, capital gains tax, and assessments following closure notices—the burden is on you to show the assessment is wrong. Under section 50(6) of the Taxes Management Act 1970, if the tribunal is not persuaded that you have been overcharged, "the assessment or statement shall stand good."

As the Upper Tribunal confirmed in Qolaminejite v HMRC [2021] UKUT 118 (TCC), the burden to displace a tax assessment rests on the taxpayer.

This means grounds that simply express disagreement are unlikely to be enough. Effective grounds in an assessment appeal explain what HMRC got wrong and what the correct position is—ideally with reference to the evidence that supports it.

Penalty Appeals

The burden in penalty cases is split. Under the framework established in Perrin v HMRC [2018] UKUT 156 (TCC) at paragraph 69 (see our case analysis), the initial burden lies on HMRC to establish that the penalty is validly imposed. Only after that does the burden shift to you to prove a reasonable excuse.

For penalties based on inaccurate returns (Schedule 24 of the Finance Act 2007), where HMRC alleges the inaccuracy was careless or deliberate, the burden of proving the behaviour is on HMRC—not on you.

This affects how grounds are drafted. Even where there is a strong reasonable excuse, the question of whether HMRC has actually proved the penalty is valid in the first place is a separate issue. Common validity challenges include: no valid notice to file was issued, penalty notices were not properly served, or the assessment was out of time.

Discovery Assessment Appeals

If HMRC has raised a discovery assessment under section 29 TMA 1970, your grounds can challenge both the validity of the assessment and the amount. Many appellants only challenge the figures and miss the jurisdictional argument entirely—whether HMRC was entitled to raise the assessment at all.

Grounds By Type Of Appeal

Every appeal turns on its own facts. The frameworks below illustrate what effective grounds typically cover, but yours will need to reflect your specific circumstances. These are examples of structure and approach—not forms to fill in.

Penalty Appeals—Reasonable Excuse

If you're appealing a penalty and claiming a reasonable excuse, the tribunal will apply the Perrin four-step test. Effective grounds in this type of appeal typically address the same framework:

  1. What the penalty is for—identify the specific obligation you allegedly failed to meet
  2. Whether the penalty is valid—are there any procedural defects? (Perrin at paragraph 69 confirms HMRC must prove this first)
  3. What happened—the facts giving rise to your excuse, in chronological order
  4. Why it was reasonable—why would a reasonable person in your position have done the same thing?
  5. What you did afterwards—once the excuse ended, how quickly did you remedy the failure?
  6. The outcome you want—cancel the penalty

Here is an example of what clear, specific grounds look like for a late Self Assessment filing penalty:

"I am appealing the late filing penalty of £100 for the tax year 2022-23. I completed and submitted my return online on 30 January 2024 but did not receive a confirmation. I believed the return had been submitted because the screen showed no error message. I only became aware the return had not been received when I received the penalty notice on 15 March 2024. I submitted the return the same day. I ask the tribunal to cancel the penalty because I had a reasonable excuse for the late filing—I reasonably believed the return had been submitted—and I remedied the failure immediately upon discovering the problem."

Compare that with weak grounds:

"I disagree with the penalty. It is unfair."

The first version tells the tribunal what happened, why it was reasonable, and what the appellant did about it. The second tells the tribunal nothing.

For more on the reasonable excuse framework, see our detailed guide. For Self Assessment penalties specifically, our SA penalties guide covers the penalty structure and appeal routes. And if your penalty relates to the High Income Child Benefit Charge, the notification trap and reasonable excuse case law are particularly relevant to your grounds.

Penalty Appeals—Disputing The Behaviour Classification

Sometimes the issue is not whether a penalty is due, but how severe it should be. Under Schedule 24 of the Finance Act 2007, the penalty percentage depends on whether the inaccuracy was careless, deliberate, or deliberate and concealed. If HMRC has classified your behaviour as "careless" or "deliberate," the burden of proving that classification is on HMRC.

Effective grounds in a case like this might include:

  • What care you took when preparing the return (records checked, adviser consulted, information provided)
  • Why the error does not meet the threshold for carelessness or deliberate behaviour
  • What the correct classification should be, and therefore what the correct penalty amount is

Assessment Appeals—Wrong Figures

If you're appealing because HMRC has assessed the wrong amount of tax, the burden is on you under section 50(6) TMA 1970. Effective grounds in this type of appeal typically cover:

  1. What HMRC assessed—the amount and the basis for the assessment
  2. What is wrong—the specific factual or legal error
  3. What the correct figure is—what you say the tax should be
  4. What evidence supports your position—documents you have or can obtain
  5. The outcome you want—reduce the assessment to £X

Here is an example of what effective grounds look like:

"HMRC assessed me on total income of £65,000 for 2022-23. This includes £15,000 which HMRC has treated as self-employment income. This amount was a loan from my brother, repaid in March 2024. I have bank statements showing the transfer and the repayment, and a signed loan agreement dated before the transfer. I ask the tribunal to reduce the assessment to reflect my actual income of £50,000."

Compare that with:

"I shouldn't owe this much tax. The figures are wrong."

The first version identifies the specific error, explains why it is wrong, and points to supporting evidence. The second gives the tribunal nothing to work with—and under section 50(6), if you don't persuade the tribunal the assessment is wrong, it stands.

Discovery Assessment Appeals

A discovery assessment under section 29 TMA 1970 allows HMRC to assess tax outside the normal enquiry process. But HMRC can only do this if certain statutory conditions are met. Your grounds can challenge whether those conditions were satisfied—not just whether the amount is correct.

Effective grounds in a discovery assessment appeal typically address:

  • The section 29(5) "staleness defence": If you included all relevant information in your tax return or accompanying documents, HMRC cannot raise a discovery assessment simply because their officer failed to read it carefully enough. Grounds raising this defence typically identify the specific information provided that should have alerted HMRC to the correct position.
  • Whether there was a genuine "discovery": Under section 29(1), HMRC must have discovered that tax ought to have been assessed but was not. Your grounds can challenge whether HMRC's "discovery" is genuine.
  • The behaviour classification: If HMRC alleges "deliberate" behaviour to access the 20-year time limit, the Supreme Court in HMRC v Tooth held that this requires intent to mislead—akin to fraud. Challenging the classification is often the strongest ground available.
  • Whether the amount is correct: Even if the assessment is valid, you can challenge the figures.

The jurisdictional challenge—whether HMRC was entitled to raise the assessment—logically comes first, because if the assessment is invalid, the amount is irrelevant.

Closure Notice Appeals

If HMRC has issued a closure notice after an enquiry into your return, the scope of your appeal is defined by the conclusions stated in the closure notice. As the Upper Tribunal held in Daarasp LLP v HMRC [2021] UKUT 87 (TCC), the wording of the closure notice matters—the tribunal will consider whether the specific conclusions in the notice are correct.

Read the closure notice carefully. Effective grounds respond to the specific conclusions stated in the notice, not to things HMRC mentioned informally during the enquiry.

VAT And Indirect Tax Appeals

VAT appeals work differently from income tax appeals. If HMRC has raised a VAT assessment under section 73 of the VAT Act 1994, the legal test is whether the assessment was made to HMRC's "best judgment." This is a lower bar than getting the figures exactly right—but HMRC must still have acted rationally and on the basis of material available to them.

Effective grounds in a VAT appeal typically address:

  • Why HMRC's assessment was not to "best judgment"—what figures HMRC used and why they are unreasonable or unsupported
  • What the correct VAT position is—your actual turnover, input tax, or exempt supplies
  • Whether you need a hardship application—unlike direct tax appeals, for indirect tax appeals the disputed tax generally must be paid before the tribunal will hear the case, unless you can show that paying would cause hardship. If you cannot pay the assessed amount, you will need to apply separately for hardship

For a full overview of the appeal routes for indirect taxes, see our guide on how to appeal to the tax tribunal.

Common Mistakes

Vague Or Generic Grounds

"I disagree with HMRC's decision" or "The penalty is unfair" tells the tribunal nothing about what the dispute is actually about. The tribunal needs to know what you disagree with and why.

Emotional Rather Than Factual

"HMRC have treated me disgracefully" may be how you feel, but the tribunal needs facts and reasons. What did HMRC decide, what is wrong with it, and what is the correct position? Clear, factual grounds are more persuasive than frustration—even justified frustration.

Failing To State What You Want

Rule 20(2)(e) requires "the result the appellant is seeking." Be specific: "cancel the penalty," "reduce the assessment to £X," "discharge the discovery assessment."

For penalty appeals: arguing that the penalty is "disproportionate" when the real question is whether you had a reasonable excuse. For assessment appeals: arguing only that "I shouldn't owe this much" without explaining what HMRC got wrong factually.

Conceding Points Worth Challenging

For discovery assessments: accepting the amount but not challenging whether HMRC were entitled to raise the assessment at all. For penalties: accepting the penalty is valid but not checking whether HMRC has proved it was properly imposed.

A Warning: The Tribunal Can Increase

Under section 50(7) TMA 1970, if the tribunal finds you have been undercharged, it can increase the assessment. This is rare in practice, but it is worth being aware of when drafting your grounds. The safest approach is to focus on what HMRC got wrong, rather than volunteering additional information that could work against you.

Can You Change Your Grounds Later?

Yes. The tribunal has the power to permit amendments to your grounds of appeal under Rule 5(3)(c) of the Tribunal Procedure Rules, which allows the tribunal to "permit or require a party to amend a document."

In practice, this means:

  • Early amendments are generally permitted freely. Before HMRC has filed their statement of case, the tribunal will usually allow changes without difficulty.
  • Later amendments face more scrutiny. After statements of case and document exchange, amendments may cause delay and prejudice to HMRC.
  • Very late amendments can be refused. In 1st Alternative Medical Staffing Ltd v HMRC [2024] UKFTT 788 (TC), the appellant tried to add a new ground seven years after filing the original appeal. Judge Poon refused the amendment, finding "inordinate delay without sufficient explanation" and that the new ground had no real prospect of success.

The lesson: get your grounds as right as you can from the start. But if you later realise you missed something important—particularly after receiving HMRC's statement of case or review conclusion—you can apply to amend. The tribunal is generally sympathetic to unrepresented appellants and will not usually refuse a reasonable, timely request.

If you've been through a statutory review, your grounds to the tribunal can be more developed than your original notice to HMRC. You will have seen HMRC's reasoning in the review conclusion letter, and you can respond to it.

Practical Tips

Keep it concise. There is no prescribed length, but for a straightforward penalty appeal, a single well-drafted paragraph is often enough. For a more complex case—a discovery assessment challenge with both jurisdictional and quantum arguments, for example—one to two pages is typical. Judges appreciate brevity. If your grounds run to more than three or four pages, consider whether everything in them is genuinely a ground of appeal rather than argument or evidence.

Paper or online—both work. The online portal has text boxes with character limits. If your grounds are longer than the box allows, you can upload a separate document—the portal provides for attachments. The paper Form T240 has a small box but explicitly says you can "enclose a separate document if you need more space." Either way, a well-structured, paginated document is easier for the judge to follow than text crammed into a form box.

Numbering helps. If you are raising multiple issues—for example, challenging both the validity of a discovery assessment and the amount—numbering each ground separately makes it easier for the tribunal and HMRC to respond to each point.

Specificity matters. "HMRC assessed £15,000 of self-employment income" is far more useful than "HMRC got my income wrong." Dates, amounts, and document references give the tribunal something concrete to work with.

Facts first, argument later. Grounds are not the place for rhetoric. The facts and the outcome you want are what matter here. Detailed argument comes later—at the hearing or in written submissions. Our hearing preparation guide covers how to present your case.

Don't attach your evidence yet. Your grounds state your case—they are not the place to submit bank statements, medical records, or correspondence. Evidence comes later, during the document exchange stage. Section 6 of the Form T240 asks for your reasons; the tribunal will give directions for exchanging evidence after HMRC files their statement of case. That said, briefly mentioning the evidence you have (as in the examples above—"I have bank statements showing the transfer") helps the tribunal understand the strength of your position.

You don't need to know the law. The T242 guidance says to include "any facts or law" you rely on—the word "any" means including just the facts is perfectly fine. If you know the relevant legislation, include it. If you don't, the tribunal will apply the correct law to the facts you provide. Judges do this routinely for unrepresented appellants.

The statement of truth matters. Section 8 of the Form T240 includes a declaration: "I believe that the facts stated in this form and any continuation sheets are true." Everything in your grounds needs to be accurate.

Late appeals are a separate question. Your grounds of appeal explain why the decision is wrong. Your reasons for the delay explain why you missed the deadline. They are different questions—our late appeals guide covers the second one.

Multiple decisions, multiple grounds. If you're appealing more than one HMRC decision—for example, late filing penalties for three tax years—address each decision separately within your grounds. The tribunal needs to know which arguments apply to which decision. Numbering or using separate paragraphs for each penalty makes this clear.

Gather your information first. Before you start writing, have to hand: the penalty notice or assessment (with its reference number and date), any HMRC correspondence including the review conclusion letter if you requested one, and a timeline of what happened. The penalty notice reference number appears at the top of the notice—the tribunal and HMRC will use it to identify your case.

Free help is available. If you're on a low income, TaxAid provides free tax advice. Tax Help for Older People helps those over 60. LITRG (Low Incomes Tax Reform Group) publishes detailed guidance. Citizens Advice can also help with tax disputes. These organisations can help you draft your grounds.

After You File

Once your appeal is filed, the tribunal will send a copy to HMRC and allocate your case to a category. For Default Paper cases, HMRC must file a statement of case within 42 days; for Standard and Complex cases, within 60 days. Basic cases skip the formal statement of case and proceed directly to a hearing. You will receive HMRC's response and further directions from the tribunal.

Your grounds of appeal have set the agenda. Everything that follows—HMRC's statement of case, the evidence exchange, and the hearing itself—flows from what you wrote. For the full roadmap of the tribunal process, see our timeline guide. For what happens next at the hearing, see our hearing preparation guide. And for what to expect after the tribunal decides, see our guide on what happens after the decision.

Filing costs £0—there is no fee to appeal to the tax tribunal—and the deadline is 30 days from the date of HMRC's decision. If you're considering settlement at any stage, strong grounds give you better leverage in negotiations.

Further Reading

This article is for informational purposes only and does not constitute legal or tax advice. For advice specific to your situation, consult a qualified tax adviser, accountant, or solicitor.

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