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UK Tax Guides

Where to start

The guides are written to be read on their own, but these reading orders work well for common situations.

  • Starting your first job: how much you can earn before paying tax, gross vs net pay, then National Insurance explained and student loan repayments.
  • Checking a payslip that looks wrong: tax codes explained, then HMRC tax refunds and P800 letters.
  • Earning over £60,000: adjusted net income and the 60% trap, then salary sacrifice and pension tax relief.
  • Going self-employed or setting up a company: self-employed tax, Self Assessment deadlines, then limited company vs sole trader and dividend tax.
  • Buying a home or selling assets: Stamp Duty, Capital Gains Tax and Inheritance Tax.

Key dates in the 2026/27 tax year

Several guides refer to the same deadlines. These are the ones that apply to most people.

DateWhat happens
6 April 20262026/27 tax year starts; new rates and allowances apply
5 October 2026Deadline to register for Self Assessment for the 2025/26 tax year if you have not filed before
31 October 2026Paper Self Assessment returns for 2025/26 due
31 January 2027Online 2025/26 returns due, with the balance of tax and the first payment on account for 2026/27
5 April 20272026/27 tax year ends; last day to use this year's ISA and pension allowances

How these guides are researched and kept current

Every guide is built from primary sources: HMRC rates and thresholds, GOV.UK guidance, legislation, HM Treasury Budget documents and, for earnings data, the Office for National Statistics. Each guide lists the publications it relies on at the end, with links, so you can check any figure against the original.

The rates in the guides come from the same data as the calculators, so a change to a threshold updates the guides and tools together. Figures are reviewed at the start of each tax year, after each Budget and when HMRC changes guidance. Where a rule has been announced but not yet taken effect, such as the April 2029 salary sacrifice change, the guides say so and give the start date.

The guides explain the rules for typical situations. They are not personal financial or tax advice; HMRC can confirm how the rules apply to you, and a regulated adviser can help with pensions and investments.

Frequently asked questions

Are these guides updated for 2026/27?

Yes. They use HMRC's 2026/27 rates and are reviewed whenever HMRC or the Treasury changes a rate or rule.

Do the guides cover Scotland and Wales?

Yes. Income tax guides cover Scottish rates separately, and the property guides cover LBTT in Scotland and LTT in Wales alongside Stamp Duty in England and Northern Ireland.

Where do the figures come from?

From official publications only: HMRC, GOV.UK, HM Treasury, legislation.gov.uk and the ONS. Each guide lists its sources.

Sources

Figures are taken from official government publications and were last reviewed on 2026-10-03.

  1. GOV.UK: Income Tax rates and Personal Allowances
  2. HMRC: Rates and thresholds for employers 2026 to 2027
  3. GOV.UK: Self Assessment tax return deadlines
  4. GOV.UK: Register for Self Assessment