Self Assessment
Self Assessment Tax Return Walkthrough
Answer one short step at a time — income, costs, pensions and dividends — and finish with a clear summary of your tax bill and payment dates.
Step 1 of 5
What you earned in the tax year, before any costs.
Everything you invoiced in the tax year, excluding VAT.
From your P60 or P45 — the tax already taken off that income.
2026/27 Self Assessment
To pay by 31 January 2028
£12,869
Income tax and Class 4 National Insurance of £12,869 less tax already paid.
Effective rate
21.7%
Key dates for 2026/27
- Register with HMRC if newly self-employed: 5 October 2027
- File online and pay the balance: 31 January 2028
- Payments on account of £6,434 each, due 31 January 2028 and 31 July 2028
Because more than £1,000 is due outside PAYE, HMRC will also ask for payments on account towards next year. Your January bill could therefore be £19,303.
Savings allowance applied: £500 · Dividend allowance: £500 · Effective rate on total income 21.7%.
What this covers
Employment, self-employment, property, savings and dividend income, the personal allowance taper, pension and Gift Aid relief, and Class 4 National Insurance. It does not cover capital gains, student loan repayments, the High Income Child Benefit Charge, voluntary Class 2 contributions, capital allowances, or foreign income. It is a planning estimate, not a filed return or personal tax advice.