HMRC Self-Assessment£100 Instant Fine31 Jan Deadline
Self-Assessment Late Filing Penalty Calculator
Calculate HMRC late tax return penalties (£100 initial fine + £10/day daily charges) and late payment interest fees under HMRC rules.
HMRC Penalty & Surcharge Estimator
Estimate late tax return fines based on months overdue
£
Estimated Penalty Breakdown:
Fixed & Daily Filing Penalties
£400
£100 Base + £300 DailyTotal Estimated HMRC Penalties
£400
Plus HMRC InterestComplete Guide to HMRC Self-Assessment Penalty System
HMRC enforces strict penalties for late submission of online Self-Assessment tax returns (deadline 31 January midnight). Penalties apply even if you have no tax to pay or have already paid your tax bill.
HMRC Late Filing Penalty Timeline
| Delay Period | HMRC Penalty Applied |
|---|---|
| 1 day late (1 February) | Instant £100 fixed penalty |
| Up to 3 months late | £10 per day for up to 90 days (Maximum £900) |
| 6 months late | Further 5% of tax owed or £300 (whichever is higher) |
| 12 months late | Further 5% of tax owed or £300 (whichever is higher) |
Frequently Asked Questions
If your online Self-Assessment tax return is 1 day late (after 31 January), you incur an instant £100 penalty. If it is 3 months late, daily fines of £10/day apply up to £900 max. At 6 months and 12 months late, additional penalties of 5% of tax owed or £300 apply.
Yes. You can appeal an HMRC late filing penalty if you have a Reasonable Excuse (e.g. serious illness, bereavement, IT failure, or severe emergency) within 30 days of receiving the penalty notice.