Missing the Self Assessment tax return deadline happens — sometimes for unavoidable reasons. HMRC provides some flexibility for genuine circumstances. But every year, a number of individuals stretch the imagination with excuses that are as far-fetched as they are ineffective.
These bizarre explanations rarely result in penalties being waived, and serve more as a cautionary tale for those thinking of delaying their submission. We explored some of the most unbelievable excuses ever submitted to HMRC, why they failed, and what they reveal about the importance of preparation. The stories may be humorous, but the consequences are serious.
Locked Out and No Way In
One of the most outrageous categories of excuses relates to being physically prevented from accessing tax information. Among the strangest was the individual who claimed that his wife was in contact with aliens and had banned him from entering the house. This fantastical story did not earn him any leniency from HMRC.
Another taxpayer said that his Self Assessment paperwork was on his yacht, which caught fire. While accidents can happen, this kind of explanation still requires proof and does not justify failing to meet the filing deadline. In a different case, someone claimed that their niece had moved in and made the house so messy that they couldn’t locate their login credentials to file their return.
These kinds of access-related excuses are rarely accepted. Whether it’s down to supernatural beliefs, maritime disasters, or domestic clutter, HMRC expects all taxpayers to store documents securely and responsibly. Paper forms, if used, should be filed away safely. Online login details should be backed up and kept confidential. Being locked out, literally or figuratively, won’t excuse a missed deadline.
Misunderstanding the Deadline
Another common theme among poor excuses is a lack of awareness. One individual went with the well-worn line: “My dog ate my tax return and all the reminders.” While this might get a laugh in primary school, HMRC won’t be amused.
Some blamed confusion about the deadline date. A person explained that they thought the due date was 31 March because their spouse had told them so. Others claimed that they never received reminder letters because their postman didn’t deliver to their home.
Unfortunately, none of these arguments carry any weight. The moment you register for Self Assessment, you’re made aware of key dates and obligations. The deadline is clearly communicated as 31 January each year. HMRC also sends email and text reminders well ahead of the filing period. Blaming poor memory, lack of mail delivery, or bad advice doesn’t change the legal requirement.
Setting up digital reminders or using a calendar tool to track tax dates is a simple and effective way to stay on top of obligations. Most importantly, don’t leave it to the last few days where the chance of mistakes or delays increases.
The Digital Breakdown Excuses
Technological issues have been a staple of late filing explanations. One person claimed their internet went down just as they were about to hit submit. Another blamed a broken laptop, while also bizarrely mentioning that their washing machine had also stopped working—though how laundry is connected to tax returns remains a mystery.
Some people have argued that they were travelling abroad during the filing deadline and couldn’t access the internet, therefore making submission impossible. These kinds of digital dependency excuses may have once held some merit, but in an age of global connectivity, they’re seen as poor planning.
Internet access is now widely available, even in many remote areas. And if you’re going abroad, HMRC expects you to file early or ensure you’ll have access to file on time. Software tools and apps enable taxpayers to complete their returns on tablets and smartphones. Waiting until the final hours and then experiencing technical issues shows a lack of preparation rather than a genuine obstacle.
The message is clear: plan ahead, start early, and don’t rely on last-minute access to technology. If something goes wrong, you’ll need to prove you took all reasonable steps to file on time.
Outlandish and Surreal Stories
While many excuses are simply weak, some enter the realm of the absurd. One individual claimed they couldn’t complete their return because they had a run-in with a cow. The story lacked detail, and needless to say, the penalty was enforced.
Another taxpayer explained that they were emotionally disturbed after watching a volcanic eruption on the news, and this distracted them so much they couldn’t focus on their return. Although real-world events can be emotionally impactful, they generally don’t qualify as a reason for missing legal deadlines.
Then there was the business owner who claimed that their company didn’t really do anything that year, so there was no point in submitting a Self Assessment. This misunderstanding is more common than it should be. Even if a business had minimal activity or generated no income, it must still submit a return if HMRC expects one. Not filing is a direct breach of this obligation.
These kinds of stories might seem amusing, but they show a real lack of understanding of tax responsibilities. More importantly, they highlight the risk of ignoring compliance under the mistaken belief that inactivity or emotional distraction offers a way out.
Why People Resort to Wild Excuses
There are several reasons individuals might invent outlandish stories rather than admitting the truth. Some panic at the last moment and believe an unusual excuse might reduce the severity of the penalty. Others might be embarrassed and hope humour will soften the blow. A few genuinely believe their situation is unique enough to warrant special treatment.
What all these cases have in common is a lack of documentation and proof. HMRC does not accept verbal explanations without supporting evidence. Even when a taxpayer has experienced a real disruption, they must provide records, witness statements, or official documents to justify a late submission.
Ultimately, these bizarre excuses are a distraction from the real issue: failing to prepare. The Self Assessment process is designed to be manageable and predictable. Filing is not meant to be a surprise.
Importance of Responsibility
The overwhelming message from HMRC is that filing on time is a legal duty. Regardless of personal circumstances, taxpayers are expected to take responsibility for their obligations. If a situation arises that genuinely prevents submission, evidence must be gathered quickly and an appeal lodged as soon as possible after the deadline.
Being proactive is the best approach. Begin preparing your tax return well in advance. Keep financial records organised. Maintain copies of correspondence from HMRC and always update your contact details with them to ensure you receive all communications. Make sure your login credentials are securely saved and accessible.
If your return is straightforward, consider using online services or mobile apps to make the task easier. If it’s more complicated, don’t hesitate to seek help. Many taxpayers benefit from using software tools that calculate totals, check for common errors, and even identify areas for potential tax savings. These tools can simplify the process and help you avoid mistakes that might delay your submission.
What These Excuses Really Teach Us
Though humorous, these unbelievable excuses highlight a serious issue—poor preparation. The stories are a reflection of last-minute panic and disorganisation. They also serve as a reminder that trying to outwit the system with a tall tale is rarely successful.
Preparing in advance, being aware of key deadlines, and having a reliable way to submit your return is far more effective than dreaming up an excuse. It saves time, reduces stress, and avoids financial penalties. Tax isn’t always simple, but excuses—especially the surreal kind—aren’t a solution.
Introduction to Reasonable Excuses
While HMRC rejects many bizarre or unbelievable reasons for late tax filing, it does accept some as reasonable. The key lies in how the excuse is presented, whether it’s supported by evidence, and whether the individual took prompt action as soon as circumstances allowed. We look at what HMRC considers a valid excuse, how to gather the right supporting information, and how to appeal a penalty effectively.
Understanding HMRC’s Criteria
A reasonable excuse, according to HMRC, is something that stopped you from meeting your tax obligations despite taking reasonable care to do so. This means the event or issue must have been unexpected or out of your control, and you must have resumed filing or payment as soon as it became possible.
Examples might include serious illness, a close family bereavement, system failures on HMRC’s end, or major life disruptions such as flooding or fire. What matters most is that the event directly prevented the taxpayer from meeting their obligations and that they acted as soon as possible once it was resolved.
Illness or Medical Emergencies
One of the most common reasonable excuses is falling seriously ill or being hospitalized close to the deadline. For instance, if someone was admitted to hospital in an emergency and remained unable to access records or complete the return until after the deadline, HMRC may accept this as a valid reason.
To make a successful appeal, supporting documentation such as hospital records, a letter from a medical professional, or evidence of treatment should be provided. It also helps if the taxpayer filed the return as soon as they were able, showing that they made every effort to meet their obligations as soon as possible. Chronic illness can also be a valid excuse if it has a direct impact on someone’s ability to manage their financial affairs. Again, it must be accompanied by appropriate evidence.
Death or Serious Illness in the Family
The death of a close relative shortly before the deadline may also count as a reasonable excuse. Grieving, dealing with funeral arrangements, or supporting other family members during such times can make it difficult to focus on administrative tasks.
In this case, HMRC typically expects the deceased to be a close family member such as a spouse, parent, or child. Death certificates, funeral orders of service, or a letter from a solicitor can help support the claim. Timeliness is important—filing as soon as possible after the disruption will help show that the taxpayer still took responsibility.
Similarly, caring for a seriously ill relative or managing a crisis at home might also be seen as reasonable, particularly when it’s documented and when the return is submitted promptly afterward.
Issues with HMRC Systems
There are cases where the problem lies not with the taxpayer, but with HMRC’s own systems. For instance, if the Government Gateway service crashes near the deadline and prevents multiple people from filing on time, this may be publicly acknowledged and taken into account when issuing penalties.
HMRC has a history of granting extensions or accepting appeals in cases of verified system failures. However, it’s crucial to take screenshots or keep a record of the technical issue, including error messages and timestamps, and to submit your return as soon as the service is restored.
Issues with receiving the Unique Taxpayer Reference (UTR) or activation codes, especially if HMRC delays sending them, may also be grounds for appeal. Document all your communication, requests, and evidence of delay to build a solid case.
Unexpected Events and Natural Disasters
Natural disasters, severe weather, or significant damage to your home or place of business can also prevent timely filing. If your records are destroyed in a fire, your property is flooded, or your location is rendered inaccessible due to snowstorms or other hazards, HMRC may treat this as a reasonable excuse.
Evidence could include photos of the damage, official weather alerts, reports from emergency services, or insurance documentation. These must clearly link the event to your inability to submit the return.
What matters most is that the event was unforeseeable and that it genuinely stopped you from filing on time. Attempting to file a return while coping with a sudden evacuation or loss of electricity would not be expected. Filing promptly once conditions improve is essential to support your claim.
Problems with Agents or Advisors
Occasionally, a taxpayer may rely on an accountant or tax adviser to handle their return. If that professional fails to submit the return on time, the taxpayer may feel justified in shifting blame. However, HMRC takes the position that responsibility ultimately lies with the individual.
That said, if the professional was suddenly taken ill, went out of business without notice, or misled the taxpayer despite their best efforts to comply, HMRC may consider this a reasonable excuse. In these cases, documentation such as email exchanges, engagement letters, or evidence of attempted follow-up may strengthen your case.
A common pitfall is failing to check that the advisor submitted the return. Even if someone is handling the return on your behalf, it’s wise to confirm that everything is on track as deadlines approach.
Postal Delays and Document Delivery Problems
While most people now submit returns online, there are still those who prefer paper forms. If a return is posted on time but delayed due to postal strikes or issues with delivery services, this may be accepted if there’s clear evidence of the delay.
Using tracked posts and keeping postal receipts is essential. If you post your return via standard mail with no proof, it becomes very difficult to prove when it was sent. HMRC does not accept postal excuses easily unless the delay was widely reported or exceptional.
The same applies to receiving forms or correspondence late. If HMRC failed to deliver crucial paperwork in time, document when the materials were received and how it impacted your ability to comply.
Mental Health and Personal Crises
Mental health challenges are increasingly recognised as a factor that can affect a person’s ability to manage their affairs. HMRC has acknowledged that depression, anxiety, or trauma may count as a reasonable excuse if properly documented.
A letter from a GP or mental health professional detailing how the condition impacted the ability to complete the return will be important. Timing is critical—the more closely the period of mental health difficulty aligns with the filing deadline, the more likely the excuse is to be accepted.
Personal crises such as divorce, domestic abuse, or sudden homelessness can also be considered. These are traumatic situations, and HMRC is more likely to be sympathetic if the taxpayer acted swiftly once stability returned.
What Doesn’t Count
It’s also important to know what excuses are rarely, if ever, accepted. These include:
- Forgetting the deadline
- Not receiving reminders
- Being abroad with no internet
- Losing login details
- Relying on someone else to submit
These scenarios point more toward poor organisation than unforeseen circumstances. HMRC’s guidance makes it clear that a taxpayer must plan for the deadline and maintain control over their responsibilities. Waiting until the last minute to file increases the risk of something going wrong—and that risk is not something HMRC typically covers.
How to Appeal a Penalty
If you’ve missed the deadline and believe you have a valid reason, the next step is to appeal. This can be done online or by post. The appeal must explain your circumstances clearly, supply supporting documents, and show that you acted as soon as reasonably possible.
When writing the appeal, include:
- Your UTR and contact details
- Date of the missed deadline
- Full explanation of the situation
- Evidence such as medical letters, police reports, or photos
Be honest and concise. Long-winded stories without clear proof are unlikely to succeed. HMRC will review your appeal and respond with a decision. If rejected, you have the right to ask for a review or appeal to the tax tribunal.
Acting quickly improves your chances. Most appeals must be made within 30 days of the penalty notice, so don’t delay. Even if you’re not sure your excuse will be accepted, it’s worth submitting a clear and well-evidenced appeal.
Preparing for the Unexpected
While nobody can predict every challenge life may throw at them, having a system in place for tax compliance helps reduce risks. Keep digital and physical copies of documents. Set up early reminders. Know your login credentials and test access ahead of deadlines.
Also, build in extra time to submit in case something unexpected does arise. That way, even if there is a disruption, you’re less likely to miss the deadline entirely. Being proactive not only avoids penalties but also reduces stress. It puts you in a stronger position if you ever do need to rely on a reasonable excuse.
Realities of Missing the Tax Deadline
While some people may try to justify a missed Self Assessment deadline with dramatic, surreal, or downright hilarious excuses, the reality for most is that missing the filing deadline comes with consequences. Once the deadline passes and no return has been submitted, HMRC’s automated penalty system starts to kick in.
Understanding how these penalties unfold, what appeals are actually accepted, and what steps you can take to put things right is essential for anyone who has missed a deadline—or fears they might. We explore what happens when you file your Self Assessment tax return late, how HMRC responds, and what you can do to mitigate or challenge penalties if your excuse genuinely holds water.
Understanding the Penalty Timeline
HMRC’s penalty system is straightforward and strict. As soon as the January 31st deadline passes without a submission, the clock starts ticking on penalties. These aren’t one-off charges—they grow the longer the return remains outstanding.
Immediate Penalty After January 31st
The first automatic penalty is a fixed £100 fine. This applies even if you owe no tax or have paid your liability in full but failed to file the return.
After Three Months
If your return is still outstanding three months after the deadline (April 30th), daily penalties of £10 begin and can accrue for up to 90 days. That’s potentially an additional £900 added to your bill.
After Six Months
At the six-month mark (July 31st), HMRC adds another penalty: the greater of £300 or 5% of the tax due.
After Twelve Months
If your return still hasn’t been submitted a year after the deadline, another penalty applies. Again, it’s £300 or 5% of the tax owed—whichever is greater. In serious cases involving deliberate withholding of information, the penalties can reach 100% of the tax due, doubling your liability.
Financial Impact of Late Filing
Penalties can build up quickly and severely affect your finances. If you miss every stage of the penalty structure and owed tax in the first place, the total penalties and interest can be substantial. Even those who don’t owe tax can still be liable for the fixed penalties simply for failing to file.
On top of these, HMRC charges interest on unpaid tax, which continues to accumulate daily until the full balance is cleared. Ignoring the problem only makes it worse.
Genuine Excuses That HMRC Accepts
Although HMRC is strict, it does make allowances for truly exceptional circumstances. Not every late return results in a penalty if you can prove you had a reasonable excuse. But the bar is set high.
Examples of Accepted Excuses
- Serious illness or death of a close relative just before the deadline
- Hospitalisation that prevented access to your records
- Fire, flood, or natural disaster that damaged your records
- Issues with HMRC’s own systems or service
- A disability or mental health condition that impacted your ability to file
These situations are not only rare but must be well documented. Evidence is key. Simply claiming one of these scenarios without proof is unlikely to result in a successful appeal.
Frequently Rejected Excuses
- Believing someone else had filed on your behalf
- Being unaware of the deadline
- Problems with internet connection or broken devices
- Having too much work or being too busy
- Confusion about your Self Assessment status
These explanations rarely succeed because HMRC expects taxpayers to take responsibility for their obligations and plan accordingly.
How to Appeal a Penalty
If you believe your excuse qualifies as reasonable, you can appeal to HMRC. There is a specific process to follow and deadlines for lodging your appeal.
Filing an Appeal
You can appeal online through your Government Gateway account or by filling out the SA370 form and posting it to HMRC. The appeal must be submitted within 30 days of receiving your penalty notice.
What to Include
To maximise your chance of a successful appeal, you should:
- Clearly state the reason you missed the deadline
- Explain why the excuse was beyond your control
- Provide documentary evidence to support your claim
- Show that you acted as soon as possible to correct the situation
The more credible and well-documented your explanation, the more likely it is HMRC will cancel the penalty.
When Appeals Are Rejected
If your appeal is rejected, HMRC will confirm this in writing. You still have the right to escalate your case. You can ask for a review of the decision by another HMRC officer or submit your case to the independent tax tribunal.
However, this process can take time and effort. Unless you’re confident in your excuse and the supporting evidence, it may not be worth pursuing. Paying the penalty may be the faster and less stressful option.
Importance of Proactivity
The best approach to avoid all of this is to be proactive. You should be preparing your tax return well before January. If you think there’s a chance something might disrupt your ability to file, take action early.
Steps to Stay Ahead
- Keep your financial records organised throughout the year
- Set calendar alerts well in advance of the January deadline
- Log in to your HMRC account periodically to ensure it’s accessible
- File your return early, even if you wait until later to pay
- Seek help from a professional if your situation is complex
Being ahead of the game eliminates the need for excuses and protects you from unexpected penalties.
Help Is Available If You’re Struggling
Sometimes, despite your best intentions, you may face difficulties filing on time due to illness, family responsibilities, or other disruptions. In these cases, it’s better to reach out than to ignore the situation.
Contact HMRC Early
If you know in advance that you might miss the deadline, you can contact HMRC to explain your situation. They may offer guidance, additional time, or a structured solution. Leaving it until after the deadline without communication is far less effective.
Use the Time to Pay Service
If you’ve filed your return but can’t pay the full tax bill, HMRC’s Time to Pay arrangement lets you set up a payment plan. This won’t remove late filing penalties, but it will help prevent late payment penalties and interest from spiraling.
Learning from Other People’s Mistakes
The wild excuses submitted each year might offer comic relief, but they also serve as a lesson. Most people don’t get away with creative storytelling. The only way to stay on the right side of HMRC is to be prepared and honest.
Being late comes with automatic consequences. Hoping for leniency based on personal anecdotes or unusual circumstances is a gamble that rarely pays off. Filing early, keeping your documents safe, and double-checking the deadline are the simplest ways to ensure you don’t find yourself in the penalty zone.
Why HMRC Takes Deadlines Seriously
HMRC manages millions of tax returns each year. The Self Assessment system relies on taxpayers submitting accurate and timely returns to ensure the smooth collection of public revenue.
Missing deadlines affects more than just your personal finances—it adds pressure on HMRC’s systems and administration. That’s why the department has built-in penalties and clear boundaries. They’re not just punitive—they’re meant to keep the system efficient and fair for all. The consistency of applying penalties helps maintain public trust and encourages timely compliance. If leniency were given too freely, it would undermine the system.
Staying Compliant Going Forward
If you’ve faced a penalty in the past, the best thing you can do is learn from the experience. Put systems in place to prevent a recurrence.
Post-Penalty Checklist
- Set new reminders for all future deadlines
- Organise your digital and physical tax documents
- Consider filing as early as October when the online window opens
- Use professional help if your circumstances have changed
Each missed return adds to your compliance risk profile. Regular lateness may prompt HMRC to investigate further or question the accuracy of your returns. Avoid the spiral by treating Self Assessment like any other crucial business or financial task. It deserves your full attention.
Conclusion
Missing the Self Assessment tax return deadline is rarely without consequences, and while HMRC does accept genuine reasons in certain cases, it has little tolerance for far-fetched stories or exaggerated excuses. Across this series, we’ve looked at the most bizarre justifications ever submitted from alien sightings to destructive pets and distracted minds. These examples, while often humorous, highlight a serious point: leaving your tax return until the last minute is a risky move that can result in fines, stress, and unnecessary complications.
The most effective way to stay compliant and avoid penalties is through preparation, organisation, and timely action. Keeping records in order, knowing the key dates, and using reliable methods to submit your return ensures you remain on the right side of HMRC without needing to come up with a creative story to explain a delay. By planning ahead, setting reminders, and maintaining consistent access to your tax information, you place yourself in the strongest position to meet deadlines without panic.
Ultimately, submitting your Self Assessment return isn’t just about fulfilling a legal obligation, it’s about taking control of your finances. It gives you clarity on your tax situation, helps you avoid penalties, and provides peace of mind. While the list of unbelievable excuses might continue to grow each year, the best way to stay out of HMRC’s spotlight is simple: file your return on time, every time.