When does the new tax year start in the UK?

The new UK tax year starts on 6 April every year. For 2026/27, the tax year officially begins on 6 April 2026 and runs until 5 April 2027. On this date, statutory tax code changes come into effect (e.g. 1257L), annual allowances reset, and statutory changes such as employer National Insurance thresholds and the £12.71/hr National Living Wage are implemented on payroll systems across England, Scotland, Wales, and Northern Ireland.

When is the budget 2025?

The UK fiscal calendar featured the Autumn Budget on 30 October 2024 and the Spring Statement on 6 March 2025 delivered by the Chancellor of the Exchequer. These landmark fiscal events introduced statutory measures including the employer Class 1 National Insurance rate rise to 15.0% above the £5,000 secondary threshold, capital gains tax rate alignments, and new statutory living wage rates taking effect from April 2025 and April 2026.

When is the next budget in the UK?

The next major UK fiscal event is the annual UK Budget delivered by the Chancellor of the Exchequer to the House of Commons, accompanied by the latest economic and fiscal forecast from the independent Office for Budget Responsibility (OBR). Major fiscal statements are traditionally presented in March (Spring Budget) or late October/November (Autumn Statement). Exact dates are confirmed by HM Treasury several weeks in advance.

What are the penalties for missing the 31 January Self-Assessment deadline?

If you submit your online Self-Assessment return after midnight on 31 January, HMRC levies an immediate, automatic £100 late filing penalty even if you have no tax to pay. After 3 months late, HMRC charges daily penalties of £10 per day up to a £900 maximum. At 6 months and 12 months, further statutory penalties of 5% of the tax due or £300 (whichever is greater) are added, plus statutory late-payment interest on unpaid tax balances.

How do Self-Assessment Payments on Account work in the UK?

Payments on account are advance payments toward your next year's income tax and Class 4 National Insurance liability. If your tax bill exceeds £1,000 and less than 80% was collected through PAYE, HMRC splits your anticipated bill into two equal 50% instalments due on 31 January and 31 July. If your earnings will be lower in the subsequent tax year, you can submit an online claim to reduce your payments on account.

UK Tax Calendar 2026/27 | Key HMRC Deadlines & Dates

UK Fiscal Statements & Chancellor Budget Tracker

Major tax legislation in the United Kingdom is announced during key parliamentary fiscal events delivered by the Chancellor of the Exchequer at the House of Commons. Below is an overview of core fiscal milestones and statutory changes:

Fiscal Event	Timing	Key Statutory Tax Measures	Affected Taxpayers
Autumn Statement & Spending ReviewPrimary Fiscal Event	Late October / November	Employer Class 1 NI increased to 15.0% and secondary threshold lowered to £5,000 (NICA 2025); Capital Gains Tax rates set at 18% basic / 24% higher; non-dom status abolition.	Employers, Business Owners, High Net Worth Individuals
Spring Budget StatementAnnual Economic & Tax Plan	Early March	National Living Wage increased to £12.71/hr; Income Tax personal allowance (£12,570) and Higher Rate (£50,270) frozen; OBR 5-year economic and inflation growth forecasts.	All UK Employees, Pensioners, Sole Traders
HMRC Real-Time PAYE Tax Code IssueAnnual Notice of Coding	February / March Annual	HMRC issues P9 coding notices to employers and individual P2 notices to employees reflecting changes in benefits in kind (P11D), pension allowances, or Marriage Allowance.	PAYE Employees & Company Payroll Teams

5 April Tax Year End Checklist: Allowances You Cannot Carry Forward

Under UK tax law, the tax year strictly closes on 5 April at 23:59:59. Unlike some business tax reliefs, personal tax allowances operate on a strict use-it-or-lose-it basis:

1. Annual ISA Allowance (£20,000)

You can shelter up to £20,000 per tax year across Cash ISAs, Stocks & Shares ISAs, and Innovative Finance ISAs (with £4,000 for Lifetime ISAs). Unused capacity is permanently lost at midnight on 5 April.

2. Pension Annual Allowance Carry-Forward

While you can carry forward unused portions of your £60,000 annual pension allowance for up to three previous tax years, 5 April is the deadline before the earliest qualifying year drops out of scope.

3. Capital Gains Tax Exemption (£3,000)

Every individual has a £3,000 annual exempt amount for capital gains under the Finance Act. Realizing taxable gains from shares, crypto, or property before 5 April crystallizes gains tax-free.

4. Marriage Allowance Backdating (£1,260 Rebate)

Couples can backdate their Marriage Allowance claim under Section 55A ITA 2007 for up to 4 prior tax years. 5 April is the absolute cut-off to claim the rebate for the earliest allowable tax year.

HMRC Self-Assessment Deadlines & Statutory Penalty Structure

Under the Taxes Management Act 1970 (Sections 59B, 8, and Schedule 55 Finance Act 2009), missing statutory Self-Assessment milestones triggers progressive fines and interest:

1 Day Late

£100 Immediate Penalty: Levied instantly at 00:01 on 1 February even if you have zero tax liability or are due a refund from HMRC.

3 Months Late

£10 Daily Fines: HMRC charges £10 for each additional day up to a maximum of 90 days (£900), bringing the total fine to £1,000.

6 & 12 Months Late

5% Surcharge: An additional penalty equal to 5% of the tax due or £300 (whichever is greater) is charged at 6 months, and again at 12 months.

Late Payments

Statutory Interest: Outstanding balances incur daily interest at the Bank of England official base rate plus 4.0% until fully settled.

Frequently Asked Questions: UK Tax Calendar & Deadlines

Clear answers based on official HMRC rules and statutory guidance.

The UK tax year ends at midnight on 5 April each year. Under the UK calendar dating back to the British calendar reforms of 1752, the 2025/26 tax year strictly finishes on 5 April 2026. This is the absolute statutory deadline for using your annual tax-free allowances, including the £20,000 ISA limit, the £60,000 annual pension allowance, the £3,000 Capital Gains Tax annual exemption, and backdating 4-year claims for Marriage Allowance.