HMRC Penalties 2026: Late Filing, Late Payment & How to Appeal
The HMRC late filing penalty starts at £100 for missing the 31 January Self Assessment deadline — even if you owe no tax. After 3 months, £10 daily penalties apply (up to £900). Late payment penalties add 5% of unpaid tax after 30 days, 6 months, and 12 months. Most penalties can be appealed within 30 days if you have a reasonable excuse.
Key Takeaways
- Missing the 31 January 2027 online deadline triggers an automatic £100 penalty
- Daily £10 penalties apply from day 91 — up to £900 total over 3 months
- Late payment penalty is 5% of tax unpaid after 30 days, again at 6 and 12 months
- HMRC charges daily interest on top of penalties — currently Bank of England base rate + 2.5%
- Gig workers earning over £1,000 must register by 5 October or face further fines
- First-time offenders may have the £100 penalty cancelled under HMRC's First Offender policy
What Are the HMRC Late Filing Penalties for 2026?
If you miss the Self Assessment filing deadline, HMRC issues automatic penalties in stages regardless of whether you owe any tax at all.
| Time After Deadline | Penalty | Cumulative Total |
|---|---|---|
| Day 1 (missed deadline) | £100 fixed penalty | £100 |
| 3 months (day 91+) | £10 per day (up to 90 days) | £1,000 |
| 6 months | 5% of tax owed or £300 (greater) | £1,300+ |
| 12 months | Further 5% of tax owed or £300 | £1,600+ |
The paper return deadline is 31 October 2026. The online Self Assessment deadline is 31 January 2027 for the 2025/26 tax year. Filing even one day late triggers the £100 penalty automatically — no warning is issued first.
"You'll get a penalty if you need to send a tax return and you miss the deadline for submitting it or paying your bill. You'll pay a late filing penalty of £100 if your tax return is up to 3 months late."
— GOV.UK Self Assessment Penalties
For gig workers on platforms such as Deliveroo, Uber Eats, Amazon Flex, or Just Eat, late filing penalties accumulate quickly. A driver who files 9 months late could face the £100 fixed penalty, £900 in daily penalties, and a 6-month surcharge — a total exceeding £1,300 before any tax is even assessed.
What Are the HMRC Late Payment Penalties?
Late payment penalties apply separately from late filing penalties. You can be penalised for both simultaneously if you file and pay late.
| Time After Payment Due | Penalty Rate | Example (£2,000 tax owed) |
|---|---|---|
| 30 days late | 5% of unpaid tax | £100 |
| 6 months late | Further 5% of unpaid tax | £200 (total £300) |
| 12 months late | Further 5% of unpaid tax | £200 (total £500) |
| Total penalties + interest | Up to 15%+ of tax owed | £500+ on a £2,000 bill |
HMRC offers a Time to Pay arrangement for those who cannot pay in full. Contacting HMRC before the deadline to set up an instalment plan can prevent late payment penalties from applying. You can arrange this online through your Government Gateway account or by calling the HMRC Payment Support Service.
Payments on Account: A Hidden Trap for Gig Workers
If your Self Assessment tax bill exceeds £1,000, HMRC requires you to make advance payments towards next year's bill — called payments on account. These are due on 31 January and 31 July each year. Missing these triggers the same late payment penalty structure as the main bill. Many first-year gig workers are caught off guard by a bill that is effectively 150% of what they expected.
Does HMRC Charge Interest on Unpaid Tax?
Yes. HMRC charges daily interest on all unpaid tax from the due date until full payment. Interest accrues in addition to late payment penalties — not instead of them.
The current HMRC interest rate for late payment is the Bank of England base rate plus 2.5%. As of early 2026, this means interest accrues at approximately 7.5% per year on any outstanding balance.
- Interest begins accruing from 1 February for January balances
- Interest is charged on unpaid penalties as well as unpaid tax
- HMRC does not cap how long interest accrues — it continues until the debt is cleared
- Interest paid to HMRC is not tax-deductible as a business expense
- HMRC sends a revised statement once interest is calculated — check your online account regularly
What Is the Penalty for Failing to Register for Self Assessment?
If you earn more than £1,000 from gig work and do not register with HMRC by 5 October following the tax year, HMRC can issue a failure-to-notify penalty of up to 100% of the tax owed.
| Behaviour | Penalty Range |
|---|---|
| Unprompted disclosure (you told HMRC yourself) | 0–30% of unpaid tax |
| Prompted disclosure (HMRC contacted you first) | 15–30% of unpaid tax |
| Deliberate non-registration | 30–100% of unpaid tax |
| Deliberate and concealed | Up to 200% of unpaid tax |
Gig workers who start earning from platforms such as Uber, Deliveroo, or Amazon Flex mid-year must register by 5 October of the following tax year. For earnings starting in the 2025/26 tax year (ending 5 April 2026), the registration deadline is 5 October 2026.
Important: HMRC receives income data directly from gig platforms under the UK's Digital Reporting rules. If you earn over £1,000 and do not register, HMRC may already know about your income before you disclose it — reducing your penalty reduction significantly.
How Do You Appeal an HMRC Penalty?
You have 30 days from the date of the penalty notice to appeal. Appeals are made online through your HMRC account or by post using form SA370. You must demonstrate a reasonable excuse.
What Counts as a Reasonable Excuse?
- Serious illness that prevented you or your agent from filing
- Death of a close relative shortly before the deadline
- HMRC system failure — documented outages on the filing deadline date
- Postal delays for paper returns sent well before the deadline
- Unexpected hospital admission covering the filing date
- Natural disaster destroying records needed to complete the return
What Does Not Count as a Reasonable Excuse?
- Forgetting the deadline or not receiving a reminder
- Being too busy with work or running a business
- Relying on someone else who did not file on your behalf
- Not having the money to pay the tax bill
- Finding the return too complicated
First Offender Policy
HMRC operates an informal First Offender cancellation for the £100 late filing penalty. If you have never been penalised before, file shortly after the deadline, and have a clean compliance record, you can request the penalty be cancelled. This is not a formal right — it is at HMRC's discretion — but is routinely granted for first-time late filers who act quickly.
How to Submit an Appeal
- Log in to your HMRC online account via Government Gateway
- Navigate to Self Assessment and find the penalty notice
- Select "Appeal this penalty" and state your reasonable excuse clearly
- If appealing by post, use form SA370 and send to the address on your penalty notice
- Keep a copy of your appeal and note the date submitted
- HMRC will respond within 45 days — if rejected, you can request a review or appeal to the Tax Tribunal
How Do Gig Workers Avoid HMRC Penalties?
The most effective way to avoid all HMRC penalties is to register early, file before the deadline, and set aside tax throughout the year rather than trying to pay a lump sum in January.
- Register by 5 October — do not wait until January to register and file simultaneously
- Set aside 25–30% of earnings monthly — use our gig worker tax calculator to estimate your bill
- File early — the online return opens in April; filing in May or June eliminates deadline risk
- Use HMRC's Budget Payment Plan — make voluntary advance payments to spread the cost
- Keep records throughout the year — mileage logs, platform earnings statements, expense receipts
- Set a calendar reminder for 31 October (paper) and 31 January (online) each year
- Contact HMRC early if you cannot pay — a Time to Pay arrangement prevents late payment penalties
For a full breakdown of allowable expenses that reduce your tax bill — and therefore reduce the size of any potential penalty — see our guide to delivery driver expenses 2026.
Frequently Asked Questions
What is the penalty for late Self Assessment filing?
Missing the 31 January deadline triggers an automatic £100 fixed penalty. After 3 months, £10 daily penalties apply up to £900. After 6 months, HMRC adds 5% of tax owed or £300 (whichever is greater).
What is the penalty for late payment of Self Assessment tax?
Late payment penalties are 5% of tax unpaid after 30 days, another 5% after 6 months, and a further 5% after 12 months. Daily interest also accrues at the Bank of England base rate plus 2.5%.
How do I appeal an HMRC penalty?
Appeal online via your HMRC account or by post using form SA370 within 30 days of the penalty notice. You must have a reasonable excuse such as serious illness, bereavement, or HMRC system failure.
What counts as a reasonable excuse for HMRC?
HMRC accepts serious illness, death of a close relative, postal delays for paper returns, HMRC system outages, and unexpected hospital stays. Forgetting the deadline does not qualify as a reasonable excuse.
Can HMRC waive penalties for first-time offenders?
Yes. HMRC operates a First Offender policy for the £100 late filing penalty. If you have a clean compliance record and file within a short period after the deadline, you can request cancellation — it is routinely granted.
What is the penalty for not registering for Self Assessment?
Failure to notify HMRC by 5 October carries a penalty of up to 100% of unpaid tax. Gig workers earning over £1,000 who have not registered should disclose unprompted to minimise penalties.
Does HMRC charge interest on top of penalties?
Yes. HMRC charges daily interest on unpaid tax from the due date at the Bank of England base rate plus 2.5%. Interest accrues separately from late payment penalties and is not tax-deductible.
Tax compliance specialist since 2017. Helped 5,000+ freelancers and self-employed workers navigate HMRC penalties and UK gig economy tax rules.