When Does the Tax Year End?

This is a surprisingly common question and one that catches people out every year. The UK tax year does not follow the calendar year and if you are self employed a landlord or completing a Self Assessment return it is essential to understand the dates properly. From my experience many late filings and incorrect returns start with confusion around when the tax year actually ends.

In this article I will explain when the UK tax year ends why it is set up that way and what it means in practical terms for your income expenses and deadlines.

The UK Tax Year End Date

The UK tax year ends on 5 April every year.

This means the current tax year runs from 6 April to 5 April the following year.

For example:

• The 2024 to 2025 tax year runs from 6 April 2024 to 5 April 2025
• The 2025 to 2026 tax year runs from 6 April 2025 to 5 April 2026

Anything you earn or receive between those dates belongs to that specific tax year.

Why the Tax Year Ends on 5 April

The reason the UK tax year ends on 5 April is historical rather than practical. It dates back hundreds of years to calendar changes and accounting practices that have simply stuck.

While it feels unusual compared to most countries it is firmly embedded in UK tax law and is unlikely to change.

What the Tax Year End Means for Income

For tax purposes income is normally taxed based on when it is received not when it is invoiced.

This means:

• Salary is taxed when it is paid
• Self employed income usually counts when payment is received if using the cash basis
• Rental income is taxed when received
• Dividends are taxed when paid
• Bank interest is taxed when credited

If income is received on or before 5 April it falls into that tax year. If it is received on or after 6 April it falls into the next one.

This timing can make a real difference to your tax bill especially if your income fluctuates or you are close to tax thresholds.

What the Tax Year End Means for Expenses

Expenses usually follow the same principle.

If you use the cash basis expenses are claimed when they are paid. If you use accruals they are matched to the period they relate to.

Most sole traders now use the cash basis by default which means expenses paid on or before 5 April fall into that tax year.

This is why timing purchases around the tax year end can matter.

The Tax Year End and Self Assessment

If you complete a Self Assessment return it will always relate to a tax year ending on 5 April.

The key deadlines are:

• 5 April – tax year ends
• 5 October – deadline to register for Self Assessment if needed
• 31 January – deadline to file the return online and pay tax

For example income earned up to 5 April 2025 is reported on the 2024 to 2025 tax return which is due by 31 January 2026.

Why This Matters in Practice

Understanding the tax year end helps you:

• Know which income goes on which return
• Avoid missing income accidentally
• Plan expenses properly
• Understand tax bills and payments on account
• Avoid confusion around deadlines

From my experience many people think in calendar years and only realise the mistake when figures do not line up.

Key takeaways

The UK tax year always ends on 5 April and runs from 6 April to 5 April the following year. While it feels unusual it is one of the most important dates to understand if you are dealing with UK tax.

Once you are clear on the tax year boundaries everything else becomes easier to follow. Most tax problems I see start not with complex rules but with simple date misunderstandings.