Telling HMRC
In your first year, register for Self Assessment by 5 October after the tax year you started in. Register late, with tax still unpaid on 31 January, and there can be a penalty for that too.
Self Assessment
Self Assessment, without the January surprise.
If you work for yourself and your takings came to more than £1,000 in a tax year, you need to send HMRC a Self Assessment tax return. It is due online by 31 January after the tax year ends, and so is the tax. Here are the dates, what you pay, and what Stoneledger does about it.
The dates
Three dates a year, and one to start.
The return and the bill
The return goes online by 31 January after the tax year ends, or on paper by 31 October, and the tax is due by 31 January. The 2025 to 2026 return and its tax are due by 31 January 2027.
Payments on account
If last year’s bill was £1,000 or more, you also pay towards next year’s: half of last year’s tax by 31 January and half by 31 July, with any balance the next January. Not if more than 80% of your tax was already taken at source.
HMRC explains them in its guide to Self Assessment tax returns and how your bill is made up.
What you pay, in 2026 to 2027
Income Tax and Class 4, on your profit.
Income Tax
On your profit after the £12,570 Personal Allowance: 20% up to £50,270, 40% up to £125,140 and 45% above. The allowance shrinks once income passes £100,000, and Scotland has its own bands.
Class 4 National Insurance
6% on profits between £12,570 and £50,270, and 2% on profits above. With profits of £7,105 or more, Class 2 is treated as paid, so there is nothing to pay for it.
The £1,000 allowance
Trading income of £1,000 or less in a year is tax free. Above it, you can take £1,000 off your takings instead of your real costs, which only helps when your costs come to less.
If you are late
It starts at £100, and it grows.
A late return
£100 the day after the deadline. After 3 months, £10 a day for up to 90 days. After 6 months, 5% of the tax due or £300, whichever is more, and the same again after 12 months.
Late tax
5% of the tax still unpaid at 30 days, again at 6 months and again at 12 months, with interest on top for every day it is late.
Under Making Tax Digital
Once you are in Making Tax Digital for Income Tax, these give way to its penalty points and its own late payment penalties. How Making Tax Digital works.
What Stoneledger does
Your tax worked out as you go, not in January.
- Your tax, as you go. Your Self Assessment worked out from your books the moment you record something: profit, allowances, Income Tax and Class 4.
- What to put aside. What the year looks like if it carries on as it is, and what to move aside each month to meet the bill.
- The dates that apply to you, including the January and July payments on account, worked out from last year’s bill.
- The few things the books cannot know, asked once, in plain English, so the figure is yours and not a guess.
- Every figure opens. Click one and you see the entries behind it. You do not have to take Stoneledger’s word for a number.
- Your tax return. Under Making Tax Digital it goes from Stoneledger once HMRC grants live access. Until then, the figures are ready for HMRC’s own service or your accountant.
What it costs
£8 a month or £50 a year. That is the whole price.
One plan, with everything in it: the books, your Self Assessment, Making Tax Digital, VAT, CIS, payroll and journals. No tiers to climb and no add-ons. 30 days free, no card needed. How that compares
Know your tax bill all year, not just in January.
Stoneledger works out your Self Assessment from your books as you go, tells you what to put aside, and shows where every number came from.