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Status at 27 October 2026: rules for the January 2027 deadline
GOV.UK says the 2025 to 2026 online return and the tax are due by 11:59pm on 31 January 2027, and that a paper return had to reach HM Revenue and Customs (HMRC) by 31 October 2026. The reasonable excuse rules below apply to late filing and late payment penalties for those deadlines. GOV.UK says new points-based penalties start from the tax year you join Making Tax Digital for Income Tax: see our penalty appeal guide.
The short version
- There is no official list of excuses that always work. HMRC’s Compliance Handbook says a reasonable excuse is something that stopped you meeting a tax obligation despite you taking reasonable care, judged on the facts of each case.
- A good excuse has four parts: a real event, that existed on or before the deadline, that actually stopped you, and that you filed or paid without unreasonable delay once it ended.
- HMRC’s own examples include a bereavement, a sudden illness or hospital stay, computer or HMRC online service failure, fire, flood or theft, and postal disruption.
- Not enough on their own, according to HMRC: pressure of work, lack of information, no reminder, a mistake on your return and not having the money.
- Tribunal cases turn on their facts. The ones below show excuses failing because there was no link to the failure, no evidence, a long delay after the excuse ended, or no check on someone relied on.
What the test is
The law is in Finance Act 2009, Schedule 55, paragraph 23 (late returns) and Schedule 56, paragraph 16 (late payment). You are not liable to a penalty if you satisfy HMRC, or a tribunal on appeal, that you have a reasonable excuse. The Handbook adds:
- The excuse must exist on or before the deadline. If it arises later, it cannot be a reasonable excuse for that failure.
- It must last until you file or pay. If it ends, HMRC treats it as continuing only if you put things right without unreasonable delay.
- Events can add up. A combination that would not each be enough alone may be a reasonable excuse together.
- It need not be unforeseeable. HMRC’s manual says the law does not require that, and tells staff to avoid the words.
The Upper Tribunal set out four questions in Perrin v HMRC [2018] UKUT 156 (TCC), which HMRC’s manual follows: what facts do you say amount to a reasonable excuse; which are proven, on the balance of probabilities (more likely than not); viewed objectively, taking your experience and situation into account, do they amount to one, and when did it stop; and did you put the failure right without unreasonable delay afterwards?
The same case says HMRC must first prove with evidence that a penalty is due, and a bare assertion in its statement of case is not enough. Only then does the burden move to you.
Examples HMRC’s own guidance accepts
| Situation | What the guidance says | Have ready (our suggestion) |
|---|---|---|
| Bereavement | GOV.UK lists a partner or close relative dying shortly before the deadline. The Handbook says the death of a partner or close relative “will normally be treated as a reasonable excuse” if it affected your ability at the time. | Date of death, relationship, what you had to deal with. |
| Sudden illness or hospital stay | GOV.UK lists an unexpected hospital stay or a serious or life-threatening illness. The Handbook says a coma, heart attack or stroke would usually be accepted. The illness must have stopped you immediately before or on the deadline and until you acted. If you knew of a hospital stay in advance, HMRC expects you to have made arrangements. | Admission and discharge dates, a letter saying what you could not do. |
| Illness of a partner or relative | The Handbook says accept it only if it took up a great deal of your time and resources and stopped you acting or arranging for someone else to. | Dates, the care you gave, why nobody else could act. |
| Mental health | GOV.UK lists delays related to a disability or mental illness. The Handbook says to explain how it affected your ability to comply, not just name it. See below. | A professional’s letter and a dated account. |
| Computer or software failure | GOV.UK lists a failure while you were preparing your online return. The Handbook says “just before or while”. | Dates, error messages, a repair record. |
| HMRC online service problem | The Handbook says it may be accepted where the service did not accept the return or you could not use it. Give the error message and date, though HMRC says it will weigh each case if you cannot. A delayed activation code counts if you registered on or before the filing date and filed as soon as it arrived. | Screenshots with date and time. |
| Fire, flood, theft or lost records | GOV.UK lists them. The Handbook says loss of records by fire, flood, theft or computer failure should normally be accepted if the information could not be replaced in time. | Crime reference, insurer’s letter. |
| Postal delay | GOV.UK lists delays you could not have predicted. The Handbook says allow enough time. It accepts disrupted post, such as fire or flood at the Post Office or industrial action, or a certificate of posting showing you posted in good time. | The certificate of posting. |
| Not knowing the rule | GOV.UK lists being unaware of or misunderstanding your obligation. The Handbook says it can count if you did your best, judged against your experience. Not being contacted by HMRC does not on its own make it reasonable. | What you did to find out. |
The Handbook also lists a delay caused by HMRC, and members of the Armed Forces on active service overseas. GOV.UK also lists relying on someone who did not send your return. That has strict conditions, covered below.
What HMRC does not accept on its own
GOV.UK says these “will not be accepted”: a bounced cheque or failed payment because you did not have enough money, finding HMRC’s online system too difficult, not getting a reminder, and a mistake on your return. The Handbook adds pressure of work and lack of information.
- Not having the money. The law says insufficient funds is not a reasonable excuse unless caused by events outside your control. The Handbook’s example is a business owner who did not file because he knew he had a large capital gains tax bill and cash flow problems. HMRC said he should have filed on time even if he could not pay, and contacted HMRC to agree a time to pay arrangement.
- Thinking you did not need to file. In Berry v HMRC [2026] UKFTT 1451 (TC) a builder believed his income was below the personal allowance so no return was needed. The tribunal quoted an earlier decision: “the Act does not provide shelter for mistakes”. HMRC’s notice to file had said a return was needed even if no tax was due.
Mental health, illness and bereavement: explain how, not just what
HMRC’s Handbook says the person, and any letters of support, should explain “not just what the reasonable excuse is” but “how that detrimentally affected their ability to comply”. It lists questions HMRC asks: what was the condition, did it affect managing your tax affairs and how, did it affect dealing with HMRC and how, and did anyone help you and what arrangements were in place.
On evidence, it says HMRC may ask for it, that the minimum is something confirming the nature of the illness, and that acceptable sources include a doctor, a mental health professional, a social care professional, or a voluntary sector organisation such as Citizens Advice or TaxAid that has checked with one of them. HMRC’s request must be reasonable and proportionate, and it should accept alternatives if what it asks for may not exist. Its worked example is a builder with post-traumatic stress disorder who filed soon after recovering, with medical evidence and an explanation. HMRC accepted a reasonable excuse.
Two cautions. For physical illness the Handbook says HMRC “would not usually accept the same reasonable excuse on more than one occasion”, because you are expected to plan for a known condition. And for fluctuating conditions it asks whether it was reasonable to expect you to put plans in place.
Agents, accountants and other people you relied on
The law says relying on another person is not a reasonable excuse unless you took reasonable care to avoid the failure. HMRC’s Handbook says you cannot claim one merely because you delegated the job. It expects you to explain what you need, set deadlines and check progress. It may work where, for example, the agent was ill or bereaved, or papers were delayed by a previous adviser.
Covid. The Handbook says that for the 31 January 2021 deadline many agents told HMRC they would struggle to have clients’ returns ready because of Covid-related work pressures, and that HMRC recognised it would have been impractical for many people to find another agent in time. HMRC also announced in 2021 that it would issue no late filing penalty for 2019 to 2020 online returns received by 28 February 2021, and no late payment penalty if tax was paid or a payment plan set up by 1 April 2021. Both are about that deadline. Our reading: Covid is not a general excuse for a later year. If it made you ill, the illness guidance applies, and you would need to show how it stopped you.
What tribunals decided
The Upper Tribunal has said (in Marlow Rowing Club v HMRC [2020] UKUT 20 (TCC), quoted in HMRC’s manual) that there is no benefit in picking from the “multitude of [First-tier Tribunal] decisions on reasonable excuse, each of which will turn on their facts”. Treat these as illustrations, not rules. Harrison is an Upper Tribunal decision; the others are First-tier Tribunal decisions.
| Case | What happened | Result |
|---|---|---|
| Harrison v HMRC [2022] UKUT 216 (TCC) | A director filed his 2014 to 2015 return, due 31 January 2016, on 13 September 2018. He had a carjacking, a crash, his mother’s cancer and death, family illness, depression and business problems, and his accountant had not filed. The penalty was £42,066.09. | Dismissed. The events happened, but he kept running complex business matters, had a draft return by September 2017 and did not sign it for a year. There was no medical evidence of depression. |
| Wals v HMRC [2025] UKFTT 1331 (TC) | A taxpayer’s chartered accountant did not file his returns for four tax years on time. Penalties totalled £4,500. | Allowed for the first year’s penalty (£100) only. After the first penalty notice the taxpayer was on notice that the accountant was failing, and there was no evidence he took it up with him or sought assurances. |
| Walker v HMRC [2023] UKFTT 865 (TC) | A taxpayer relied on her husband to file. Penalties of £1,300. | Allowed because HMRC did not prove it served the notices. The tribunal added she would not have had a reasonable excuse: she had not checked her online account. |
| Berry v HMRC [2026] UKFTT 1451 (TC) | A paper return due 31 October 2024 reached HMRC on 21 April 2026. | Dismissed for the £100, £900 daily and £300 six-month penalties. A mistake is not an excuse, and he did not file even after HMRC told him to. |
In Harrison the Upper Tribunal contrasted a case, AZ v HMRC [2011] UKUT 17 (TCC), where a consultant psychiatrist’s evidence showed a robbery victim’s mental state caused “avoidance symptoms”, meaning avoiding all correspondence to do with the Inland Revenue. It said mental health problems can amount to a reasonable excuse, which HMRC accepts, but it depends on the evidence. We have only Harrison’s description of AZ, not the decision itself.
Our reading of what the cases show:
- An excuse has to explain the whole period, not just the deadline. In Harrison and Berry the delay after any excuse ended sank the case.
- If your excuse is health, evidence matters.
- If you rely on someone, check what they did, and check again after the first penalty.
- Once you know about a penalty, filing quickly helps more than arguing.
For how to put this in an appeal, see how to appeal online or on form SA370.
Our kit
The HMRC Self Assessment Penalty Appeal Pack has a decision checklist built on these questions, an evidence checklist, a timeline worksheet and letter templates for the common excuses. It does not send anything to HMRC and does not guarantee a result.
Frequently asked questions
Is being too busy a reasonable excuse?
Not on its own. The Handbook lists pressure of work as something HMRC will not normally accept alone. Look for what actually stopped you filing.
Do I need evidence?
The Handbook says the onus is on you to provide evidence, though HMRC’s requests must be reasonable and proportionate. Form SA370 asks for evidence “where possible” if you tick “other acceptable excuse”.
Can I use the same excuse every year?
HMRC’s manual says it would not usually accept the same reasonable excuse for physical illness more than once, because you are expected to plan. Each case still depends on its facts.
What if my excuse ended weeks before I filed?
HMRC treats it as continuing only if you filed without unreasonable delay. There is no set number of days. It is judged objectively, taking your situation into account.
Sources
Last checked 27 October 2026.
- Disagree with a tax decision or penalty: reasonable excuses and Self Assessment tax returns: deadlines, GOV.UK
- Compliance Handbook: Reasonable excuse (CH160000), including CH160100, CH160200, CH160300, CH160400, CH160500, CH160600, CH160700, CH160800, CH160900 and CH160950, HMRC internal manual
- Penalties for Making Tax Digital for Income Tax, GOV.UK
- Finance Act 2009, Schedule 55 and Schedule 56, legislation.gov.uk
- [Harrison v HMRC [2022] UKUT 216 (TCC)](https://caselaw.nationalarchives.gov.uk/ukut/tcc/2022/216), [Wals v HMRC [2025] UKFTT 1331 (TC)](https://caselaw.nationalarchives.gov.uk/ukftt/tc/2025/1331), [Walker v HMRC [2023] UKFTT 865 (TC)](https://caselaw.nationalarchives.gov.uk/ukftt/tc/2023/865) and [Berry v HMRC [2026] UKFTT 1451 (TC)](https://caselaw.nationalarchives.gov.uk/ukftt/tc/2026/1451), National Archives Find Case Law
- No Self Assessment late filing penalty for those who file online by 28 February and More help for Self Assessment taxpayers, GOV.UK, 2021
Changes to this guide
- 27 October 2026: Published.
This guide is general information written from the official sources listed above and checked on 27 October 2026. It is not legal, tax or financial advice, and Plainfiles is not endorsed by any government body. Rules change, so check the linked official pages for your own situation. Written and designed by Plainfiles with the help of artificial intelligence (AI) tools, then checked against the official legislation and guidance listed in the sources. How we write and check our guides.