The 31 January 2026 deadline passed over five weeks ago. As of 1 March 2026, HMRC is now charging £10 per day on top of the £100 initial penalty. Every day you wait costs you another tenner.
The fastest way to stop it: File your return today. Even with estimated figures. You can amend later.
Here's how self-assessment late filing penalties stack up:
| When | What happens | Cumulative cost |
|---|---|---|
| 1 February 2026 | £100 automatic penalty (even if no tax owed) | £100 |
| 1 March 2026 | Daily penalties begin: £10/day for up to 90 days | £100 + £10/day |
| Today () | You're days into daily penalties | |
| 31 May 2026 | Daily penalties end (90 days max = £900) | £1,000 |
| 1 August 2026 | 6-month penalty: £300 or 5% of tax due (whichever greater) | £1,300+ |
| 1 February 2027 | 12-month penalty: another £300 or 5% (serious cases up to 100%) | £1,600+ |
This is the single most important thing. Filing stops the daily penalties on the day you submit.
Don't have your exact figures? That's not a reason to wait. HMRC explicitly allows you to file with reasonable estimates and amend your return later. A filed return with estimates is infinitely better than no return at all.
Go to HMRC online services and log in. Navigate to Self Assessment → Complete your tax return.
If you've lost your Government Gateway details, you can recover them online. If you've never registered, do it now — though it will take time for your UTR and activation code to arrive.
For a basic self-employed return, you need:
Save your submission reference. This is your proof of filing date — it's what stops the penalty clock.
If you owe tax but can't pay in full, set up a Time to Pay arrangement. HMRC is generally willing to agree payment plans, especially if you contact them before enforcement action starts.
Possibly — if you have a reasonable excuse. See our complete guide to reasonable excuses for what HMRC accepts and how to appeal.
Common reasonable excuses:
Not reasonable excuses: "I forgot", "I was busy", "I didn't have the money", "I found it confusing".
Filing and paying are separate obligations. You can and should file even if you can't pay.
Options if you can't pay:
If you've never filed before and don't have a UTR or Government Gateway account, you're in a trickier position because registration takes time. But you still need to act:
For a complete walkthrough of the registration and filing process, see our first self-assessment guide.
Every day you don't file costs £10. The maths is brutal and simple:
There is no scenario where waiting helps. File now, sort the details later.
The Getting-Paid Toolkit includes tax checklists, penalty appeal templates, HMRC letter wording, and step-by-step guides to get your freelance finances back on track.
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