What are the start and end dates of the UK tax year?

Full answer

The UK tax year, sometimes called the fiscal year, runs from 6 April to 5 April the following year. For example, the 2026/27 tax year started on 6 April 2026 and ends on 5 April 2027. Why does it start on 6 April? The odd date traces back to the adoption of the Gregorian calendar in Britain in 1752. The old tax year started on 25 March (Lady Day, the old New Year). When 11 days were lost in the calendar switch, the Treasury moved the start date forward to preserve a full year of tax collection -- eventually settling on 6 April by 1800. Why the tax year dates matter: - ISA allowances: the £20,000 annual ISA subscription limit resets on 6 April each year. Unused allowance is lost -- it cannot be carried forward. - Pension annual allowance: the £60,000 pension annual allowance is calculated per tax year. Carry-forward rules reference the three preceding tax years. - Capital gains tax annual exempt amount: the CGT annual exempt amount (currently £3,000 for 2026/27) resets each 6 April. Unused exemption cannot be carried over. - Personal allowance: your £12,570 personal allowance applies to the tax year as a whole. Income is assessed across the full year. - Self Assessment deadlines: the 31 January online filing deadline relates to the tax year ending the previous 5 April. Practical tip: If you are approaching the end of a tax year, review whether to make additional pension contributions, use remaining ISA allowance, realise capital gains up to the exempt amount, or make charitable donations to maximise Gift Aid relief in the current year.

Related guides

• Uk Self Assessment Guide

More answers

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