Millions of people across the UK are being urged to act quickly after HM Revenue and Customs confirmed that fines of up to £900 will begin from 31 January for those who fail to meet key tax obligations.
The warning applies to a wide range of taxpayers, including self-employed workers, landlords, side-hustlers, and even some people who believe they “don’t earn enough to worry about tax”. With the deadline now close, HMRC has made it clear that late action will come at a cost.
This article explains exactly who will be hit, how the £900 fines build up, and what you can still do right now to avoid penalties.
Why HMRC Is Issuing £900 Fines
Every year, HMRC sets firm deadlines for people who need to submit a Self Assessment tax return and pay any tax owed. The 31 January deadline is one of the most important dates in the UK tax calendar.
HMRC says the £900 figure reflects multiple penalties stacking up over time, not a single one-off fine. If you miss the deadline and continue to delay, charges can rise quickly.
According to HMRC, these fines are not new, but enforcement is now being applied more strictly as the department cracks down on late and missing returns.
The 31 January Deadline Explained
The 31 January deadline covers two main requirements:
- Submitting your online Self Assessment tax return
- Paying any tax owed for the previous tax year
If either of these is missed, penalties can apply — even if you owe no tax at all.
This often comes as a shock to people who assume fines only apply when money is owed. HMRC has confirmed this is not the case.
Who Is Most Likely to Be Hit by the £900 Fines
HMRC has identified several groups who are most at risk of being fined.
These include:
- Self-employed workers and freelancers
- Landlords earning rental income
- People with side income from online sales or gig work
- Anyone who earned over £1,000 from additional income
- New self-employed individuals unaware they needed to register
- People who missed earlier HMRC letters or emails
If you fall into any of these categories and have not submitted your return, you could be affected.
How the £900 Fine Builds Up
The £900 figure does not appear overnight. It grows in stages if deadlines are ignored.
Here is how it usually works:
- £100 fixed penalty for missing the deadline
- After 3 months, daily penalties of £10 per day (up to £900)
- After 6 months, additional penalties may apply
- After 12 months, further fines or percentage-based charges can be added
This means someone who delays for several months could easily reach the £900 level — even if their tax bill is small or zero.
Even Zero Tax Returns Can Be Fined
One of the biggest misunderstandings is that you are safe if you do not owe any tax.
HMRC has clearly confirmed this is false.
If you were required to submit a Self Assessment return and failed to do so, penalties apply regardless of whether tax is owed.
This has caught out thousands of people in recent years, especially those with low or irregular income.
HMRC Letters and Warnings Explained
HMRC usually sends multiple reminders before fines escalate. These may include:
- Letters posted to your registered address
- Emails warning of upcoming deadlines
- Messages in your online HMRC account
However, HMRC says not receiving a reminder is not an excuse. Responsibility remains with the taxpayer.
If your contact details are out of date, you could miss warnings and still face penalties.
What Counts as Self-Employed Income
Many people wrongly believe they are not self-employed.
You may need to file a return if you earned money from:
- Freelance or contract work
- Selling goods online
- Providing services outside PAYE
- Renting out property or a room
- Content creation or affiliate income
If your extra income exceeded £1,000 in the tax year, HMRC may expect a return.
Landlords Face Particular Scrutiny
Landlords are among the most closely monitored groups.
Even if your rental income was modest or offset by expenses, HMRC still requires accurate reporting.
Failure to declare rental income can trigger fines, interest, and further investigations.
Payment Problems Do Not Stop Fines
If you cannot afford to pay your tax bill, HMRC advises contacting them before the deadline.
HMRC offers a Time to Pay arrangement that allows you to spread payments over time.
However, this does not automatically stop late filing penalties if the return itself is not submitted.
Submitting the return on time is still essential.
What To Do If You Cannot File on Time
If you know you will miss the deadline, acting early can help reduce penalties.
Steps you should take immediately:
- Submit your return as soon as possible
- Contact HMRC to explain your situation
- Check if you qualify for reasonable excuse consideration
- Arrange a Time to Pay plan if needed
HMRC may reduce penalties in limited cases, but only if you act promptly.
Reasonable Excuse Rules
HMRC may consider cancelling penalties if you can prove a genuine reason, such as:
- Serious illness
- Bereavement
- Technical failure close to the deadline
- Unexpected personal crisis
However, ignorance of the rules or forgetting the deadline is not accepted as a reasonable excuse.
How to Check If You Need to File
If you are unsure whether you must submit a Self Assessment return, HMRC provides an online checker.
You should check if you:
- Had untaxed income
- Earned money outside PAYE
- Received rental income
- Claimed Child Benefit with high income
- Made capital gains
If in doubt, it is safer to check than risk fines later.
Digital Accounts Are Now Essential
HMRC increasingly expects taxpayers to manage obligations online.
Having an active Government Gateway account makes it easier to:
- File returns
- View penalties
- Receive messages
- Arrange payment plans
Those who delay setting up accounts often struggle close to the deadline.
Why HMRC Is Being Stricter This Year
HMRC says enforcement is tightening due to:
- Increased online trading
- Growth of gig and freelance work
- Pressure to close the tax gap
- Improved data-matching systems
This means fewer people are slipping through the net.
What Happens If You Ignore the Fines
Ignoring HMRC penalties can lead to serious consequences, including:
- Interest charges
- Debt collection action
- County Court judgments
- Impact on credit records
HMRC has confirmed it will pursue unpaid penalties, even years later.
Key Actions to Take Before 31 January
To protect yourself, you should:
- Confirm whether you need to file
- Submit your return before the deadline
- Pay what you can, even if not in full
- Contact HMRC if you are struggling
Early action is the single most effective way to limit penalties.
Final Warning for UK Taxpayers
The £900 fines starting from 31 January are real, enforceable, and avoidable.
HMRC has made it clear that responsibility lies with the taxpayer, not reminder letters or emails.
If you think this does not apply to you, it is still worth checking now. A few minutes today could save you hundreds of pounds in fines later.