When does the 2026/27 tax year start and end?
The 2026/27 tax year runs from 6 April 2026 to 5 April 2027. Every UK tax year follows this same 6 April to 5 April pattern, and it's the period HMRC uses for Income Tax, National Insurance, ISA allowances, Capital Gains Tax, and most other personal tax rules.
Why does the tax year start on such an odd date?
The commonly cited explanation traces back to a calendar change in 1752, when Britain switched from the Julian to the Gregorian calendar and “lost” 11 days overnight. The tax year at the time ended on Lady Day, 25 March. To avoid collecting 11 fewer days of tax revenue, the Treasury moved the year-end to 5 April instead, and a further calendar adjustment in 1800 pushed it on by one more day to 6 April, where it has stayed ever since.
What actually changes on 6 April?
A new tax year means a fresh set of rates and allowances take effect, usually announced in the preceding Budget or Autumn Statement. For most employees, the main things that reset or change are:
- The Personal Allowance and Income Tax bands - currently £12,570 tax-free, then 20% up to £50,270 and 40% up to £125,140 in England, Wales and Northern Ireland.
- National Insurance thresholds - employee NI is currently charged at 8% between £12,570 and £50,270, and 2% above that.
- National Minimum Wage and National Living Wage rates - currently £12.71 an hour for workers aged 21 and over.
- Student loan repayment thresholds, for each plan type.
- ISA, pension and Capital Gains Tax allowances.
- Your tax code, if HMRC has updated your Personal Allowance or benefits-in-kind.
None of this happens automatically mid-year. If a Budget changes a rate partway through a tax year, it normally still only takes effect from the following 6 April, which is why payslips tend to look identical from month to month until a new tax year begins.
Key deadlines in the 2026/27 tax year
- 6 April 2026 - the 2026/27 tax year begins; new rates and allowances take effect.
- 31 January - the online Self Assessment filing deadline and balancing payment date for the tax year that ended the previous 5 April, plus the first payment on account for the current tax year, if applicable.
- 5 April - the last day to use any ISA allowance, pension annual allowance or Capital Gains Tax exemption before it resets; also the last day of the tax year itself.
- 31 July - the second Self Assessment payment on account for taxpayers who make them.
Self Assessment deadlines are easy to mix up: the 31 January deadline is always for the tax year that ended the previous 5 April, not the one still in progress. If you're filing for the 2025/26 tax year, for example, that return is due by 31 January 2027.
Why the tax year matters for your take-home pay
Your payslip is calculated cumulatively across the tax year, so your tax code, Personal Allowance and National Insurance thresholds all reset at the same point, 6 April. If your salary or circumstances haven't changed, your take-home pay from your first 2026/27 payslip should match whatever the new rates work out to. If it looks different from what you expect, it's worth checking your tax code and running your numbers through a calculator built on the current year's figures.