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When Does the New Tax Year Start in 2025?

April 3, 2025

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Understanding the timing of the UK tax year is essential for anyone looking to stay financially organised and compliant.

Whether you’re employed, self-employed, or managing a business, knowing when the new tax year starts allows you to take full advantage of allowances, submit returns on time, and optimise your tax planning.

In the UK, the tax year does not follow the calendar year, which can be confusing at first glance. However, being aware of key tax deadlines helps you stay ahead of obligations.

When Does the New Tax Year Start in 2025?

The UK tax year starts on Sunday, 6 April 2025. This marks the beginning of a new financial reporting period for income tax, National Insurance contributions, and other HMRC-related obligations.

Every individual and business operating within the UK taxation system adheres to this fixed schedule. The tax year runs from 6 April to 5 April the following year, ending on Saturday, 5 April 2026.

This date is significant for employees, employers, self-employed individuals, and investors alike. It resets annual tax allowances and often reflects changes in tax rates and bands.

For those managing finances or preparing for tax returns, it’s the anchor point for financial documentation and compliance.

Planning from this date helps streamline financial activity and prevents missed deadlines throughout the fiscal year.

Why Does the UK Tax Year Start on 6 April?

Why Does the UK Tax Year Start on 6 April

The unusual start date of the UK tax year, 6 April, dates back to the switch from the Julian to the Gregorian calendar in 1752.

During this shift, 11 days were “lost” to correct calendar inaccuracies, moving the start of the financial year from 25 March to 6 April.

Key Reasons Include

Historical roots: The original start of the financial year was the old quarter day of 25 March.
Calendar reform: The calendar correction in 1752 pushed it forward to 6 April to maintain tax collection cycles.
Consistency: The date has remained unchanged to ensure stability across government and economic systems.
Administrative convenience: Updating the date now would involve major legislative and systemic reforms.

While it might seem odd by modern standards, this historical date provides consistency for HMRC, businesses, and individuals alike.

How Is the UK Tax Calendar Organised for Employers and Employees?

The UK tax calendar is meticulously structured to support both employers and employees throughout the tax year.

For employers, it begins with updating payroll systems in line with new PAYE tax codes, income tax bands, and National Insurance thresholds. Real Time Information (RTI) submissions are made to HMRC every time wages are paid.

Employees receive updated tax codes reflecting changes in personal allowance or benefits. These codes influence how much tax is deducted from each payslip.

Year-end documents like the P60, summarising earnings and tax paid, are issued shortly after the tax year ends. Additionally, any benefits in kind are documented via P11D forms.

Both parties rely on this calendar to remain compliant. Missing PAYE or submission deadlines can result in penalties or investigations.

Therefore, aligning payroll activities with HMRC’s official tax calendar ensures smooth financial operation throughout the year.

When Does the 2024/25 Tax Year End?

The 2024/25 tax year ends on Saturday, 5 April 2025. This is the cut-off point for all income, allowances, and reliefs used within the tax year.

If you’re looking to maximise your ISA allowance, claim pension contributions, or make charitable donations, this is your last opportunity to do so for this cycle.

Employers will finalise payrolls and issue year-end tax documents such as P60s shortly after this date. Self-employed individuals and small business owners often use this period to close accounts, record expenses, and begin preparing their tax returns for submission.

After 5 April, any income or deductions are applied to the 2025/26 tax year, starting the very next day.

Being proactive before this date ensures you’re not missing out on valuable tax-saving opportunities and allows for a smoother financial transition into the next cycle.

What Key Income Tax Rates and Bands Will Apply in the 2025 Tax Year?

What Key Income Tax Rates and Bands Will Apply in the 2025 Tax Year

Knowing your income tax band helps you plan your finances efficiently. The tax bands for the 2025 tax year are expected to follow the government’s existing framework, unless changes are introduced in the Budget.

Expected 2025/26 tax bands (England, Wales, NI)

Personal Allowance: £12,570 (tax-free)
Basic Rate (20%): £12,571 to £50,270
Higher Rate (40%): £50,271 to £125,140
Additional Rate (45%): Over £125,140

Important to Know

Scottish taxpayers follow different bands due to devolved tax powers.
If your income exceeds £100,000, your personal allowance reduces.
Adjustments to these figures are typically announced during the Spring Budget.
Check gov.uk regularly to verify updates.

Understanding your band helps with salary negotiations, tax planning, and managing deductions like student loans or pension contributions.

How Does the Start of a New Tax Year Affect Self-Assessment?

For self-employed individuals, landlords, or anyone with untaxed income, the new tax year begins a fresh accounting period.

From 6 April 2025, you’ll be reporting on all income earned between 6 April 2025 and 5 April 2026 for your next return.

Key Impacts

The paper return deadline is 31 October 2025.
The online return deadline is 31 January 2026.
Advance payments (payment on account) may be due 31 July 2025.
New income and expenses must be tracked from 6 April.

Tips for Managing Your Self-assessment

Start tracking invoices, receipts, and expenses from day one.
Use accounting software or HMRC’s Making Tax Digital tools.
Stay on top of deadlines with digital reminders.
File early to avoid stress and penalties.

Planning from the start of the tax year keeps your finances in order and reduces the chance of costly errors.

What Does the New Tax Year Mean for PAYE Employees?

What Does the New Tax Year Mean for PAYE Employees

If you’re employed under the PAYE system, the new tax year may bring changes to your tax code, personal allowance, or benefits in kind. These updates are applied directly through your payroll from 6 April 2025 onward.

Your employer will receive your revised tax code from HMRC, and your payslips will reflect any adjustments in tax thresholds or reliefs.

You may notice slight changes in your take-home pay depending on updated National Insurance limits or pension contributions.

At this point, you’ll also receive a P60 summarising your previous tax year’s earnings and deductions. It’s important to check your tax code for accuracy and notify HMRC if your employment or personal circumstances have changed.

Being proactive ensures that you’re not overpaying or underpaying tax as the new financial year begins.

What Financial Planning Should You Consider at the Start of a New Tax Year?

The beginning of the tax year is an ideal time to review your finances and take strategic actions that maximise your tax efficiency.

Recommended Planning Actions

Maximise ISA contributions: Use your £20,000 annual limit early.
Top up your pension: Contribute before hitting annual limits for tax relief.
Review your tax code: Make sure HMRC has up-to-date information.
Claim any eligible tax reliefs: Including for working from home or professional fees.
Use Capital Gains Tax allowance: Dispose of assets early to utilise the annual exemption.

Also Consider:

Re-evaluating savings goals and emergency funds.
Planning big purchases or investments in line with tax treatment.
Consulting with a financial adviser for tailored advice.
Organising receipts, invoices, and financial documents from day one.

These steps set a solid financial foundation for the year ahead and help reduce surprises at tax time.

How Can You Stay Compliant with HMRC Deadlines in 2025?

How Can You Stay Compliant with HMRC Deadlines in 2025

Staying compliant with HMRC’s deadlines is key to avoiding fines and keeping your financial record clean.

Key 2025 Deadlines

6 April 2025: New tax year begins
31 July 2025: Second payment on account due (if applicable)
5 October 2025: Deadline to register for self-assessment
31 October 2025: Paper self-assessment deadline
31 January 2026: Online self-assessment and final payment deadline

Best Practices to Stay on Track

Set digital reminders in your calendar.
Use HMRC’s personal tax account and mobile app.
Maintain all receipts and income documentation throughout the year.
Engage an accountant or tax advisor if your affairs are complex.

Being organised ensures that you’re not scrambling during deadline week and can take advantage of all eligible tax reliefs.

Where Can You Find Official Guidance About the 2025 UK Tax Year?

The best source of tax-related information is always gov.uk, HMRC’s official website. It offers accurate, regularly updated resources covering personal tax, PAYE, self-assessment, VAT, and business obligations.

You can also rely on well-established third-party platforms like Sage, Tax Advisory Partnership, and Your Company Formations, which provide detailed guides and tools for tax planning and compliance.

Signing up for HMRC’s email alerts or using their digital personal tax account ensures you never miss an update.

These tools provide deadline reminders, refund status updates, and tax code changes, all in one place. Bookmarking these trusted sources will help you stay informed and compliant all year round.

Conclusion

As the UK prepares to enter a new tax year on 6 April 2025, it’s essential to stay ahead of key dates, policy changes, and planning opportunities.

Whether you’re employed, self-employed, or managing a team, starting the tax year on the right foot helps you remain compliant, avoid fines, and optimise your financial future.

From understanding tax bands to submitting returns, the earlier you prepare, the smoother your year will go. Make use of the available resources and revisit your plans as needed.