When Does the UK Tax Year Start and End?

The UK tax year doesn’t follow the calendar year—it runs from 6 April to 5 April the following year. This date is more than just a quirk of history. It sets the timeline for personal tax, self-assessment, ISAs, pensions and more.

Whether you're employed, self-employed or managing company accounts, knowing when the tax year begins and ends—and the key deadlines in between—can help you stay on top of your finances, avoid penalties and make better tax planning decisions.

What Is the UK Tax Year?

The tax year is the official 12-month period HMRC uses to assess income, benefits and deductions. It determines when income becomes taxable and when allowances reset.

Most personal tax calculations, including income tax, capital gains tax, ISA allowances and pension contributions, are linked to this timeframe.

What Date Does the Tax Year Start and End?

The current UK tax year runs from 6 April 2024 to 5 April 2025.

This start and end date applies to:      

• PAYE tax for employed workers

• Self-assessment for sole traders and landlords

• ISA and pension allowances

• Student loan repayments

• Capital gains tax

• Child benefit tax charge (if applicable)

These dates haven’t changed for centuries and remain the basis of the entire personal tax system in the UK.

Why Is the Tax Year Important for the Self-Employed?

For self-employed people, the tax year determines the period in which profits must be declared to HMRC. Self-assessment tax returns are based on this timeline, and so are national insurance contributions and payments on account.

If you’re self-employed, you’ll need to track all income and expenses that fall between 6 April and 5 April and submit your return based on this window.

It’s also your opportunity to maximise deductions or allowances before the deadline. Once 5 April passes, that year’s allowances are gone.

All Tax Dates and Deadlines to Know

• 6 April: New tax year starts

• 31 July: Second payment on account deadline (for some self-employed taxpayers)

• 5 October: Deadline to register for self-assessment if you’ve never filed before

• 31 October: Deadline for paper tax returns

• 30 December: Deadline to file online and have tax collected via PAYE (if eligible)

• 31 January: Deadline to file online tax return and pay any tax owed

Missing the 31 January deadline can result in an automatic £100 fine, with additional penalties for ongoing delays.

Deadlines for Submitting VAT

If you’re VAT registered, your deadlines depend on your VAT accounting period, but most businesses submit quarterly. Deadlines are usually:

• One calendar month and seven days after the end of each VAT period

• Payment is due at the same time as submission

Making Tax Digital for VAT is now mandatory, meaning VAT returns must be filed using compatible software unless you're exempt.

Does the Tax Deadline Include Making Payments?

Yes. HMRC expects tax returns and any tax owed to be paid by the same date. For self-assessment, that means 31 January for both filing and payment. If you miss the payment deadline, interest and penalties apply immediately.

If you can’t pay on time, contact HMRC as soon as possible. You may be able to set up a Time to Pay arrangement, spreading your bill over several months to avoid further penalties.

What Should I Do If I Can’t Pay on Time?

If you're struggling to pay your tax bill, don't ignore it. You should:

• Contact HMRC via the Self Assessment Payment Helpline

• Request a payment plan through your HMRC online account

• Avoid taking on high-interest debt to pay your bill unless you’ve explored alternatives

Time to Pay arrangements are usually available if you owe under £30,000 and are up to date with your filings.

What Is the First Day You Can Submit a Tax Return for the Previous Year?

You can start submitting your tax return from 6 April, the day the new tax year starts. For example, you can begin submitting your 2024/25 return on 6 April 2025.

Filing early doesn’t mean you have to pay early—the payment deadline is still 31 January. But submitting early gives you more time to budget and can result in quicker refunds if you're owed money.

Should I Submit My Tax Return Early?

Yes, in most cases. Submitting early gives you:

• Peace of mind

• More time to plan for your bill

• Faster access to refunds

• The chance to apply for loans or mortgages with an up-to-date tax summary

It also helps avoid last-minute stress and potential errors in January.

What Is Making Tax Digital?

Making Tax Digital (MTD) is HMRC’s initiative to modernise the tax system. It requires businesses and individuals to keep digital records and submit tax data via compatible software.

Currently, MTD is mandatory for:

• VAT-registered businesses (regardless of turnover)

It will be expanded to include self-employed people and landlords earning over £50,000 a year from April 2026, with a lower threshold of £30,000 expected from April 2027.

Steps You Can Take Before the Tax Year Ends to Reduce Your Tax Bill

If you're approaching 5 April and want to reduce your tax liability, consider:

• Maximising your ISA allowance

• Making pension contributions (which can reduce income tax)

• Offsetting losses if you're a sole trader

• Advancing business expenses or charitable donations

• Reviewing your tax code and personal allowance

• Transferring unused marriage allowance to your spouse, if eligible

Good record-keeping and early planning are key to making the most of your allowances and avoiding unnecessary tax.

Final Thoughts

The UK tax year runs from 6 April to 5 April, and this calendar affects everything from income tax to ISAs, student loans and self-employed accounts. Knowing the key dates and deadlines can help you stay ahead, avoid penalties, and take full advantage of tax planning opportunities.

Whether you’re an employee, sole trader or landlord, understanding the structure of the tax year—and acting before it ends—puts you in the strongest position financially.