End of Tax Year 2025 – Essential Deadlines for Self Assessment

The UK tax year 2024/25 concluded on 5 April 2025, marking the end of a period that began on 6 April 2024. For millions of individuals with Self Assessment obligations, this transition brings specific deadlines that must be met to avoid penalties. Understanding when the tax year ends and what it means for your tax affairs is essential for staying compliant with HMRC requirements.

The 2025/26 tax year has now begun, running from 6 April 2025 through 5 April 2026. This follows the standard UK fiscal year structure, which has been in place since the 1800s. Whether you are employed, self-employed, or receive income from property, the end of the tax year triggers specific reporting obligations and planning opportunities that should not be overlooked.

When is the end of the tax year 2025 in the UK?

The tax year 2024/25 ended on 5 April 2025 in the United Kingdom. This date is fixed by statute and has remained consistent across the fiscal calendar. The previous tax year, which began on 6 April 2024, officially closed at midnight on this date, making it the point at which income earned during that period becomes subject to final calculations and reporting.

For many taxpayers, this date carries particular significance because any income, reliefs, or allowances that were specific to the 2024/25 tax year cannot be carried forward indefinitely. The end of the tax year also triggers deadlines for reporting income from the previous year through Self Assessment, with distinct dates applying depending on whether you file online or on paper.

Overview of key dates around the tax year end

Key insights for taxpayers

• The tax year ends on 5 April and begins again on 6 April, following an established pattern that spans more than 180 years
• Paper tax returns for 2024/25 must reach HMRC by 31 October 2025
• Online submissions for 2024/25 close on 31 January 2026
• Those registering for Self Assessment for the first time must do so by 5 October 2025
• Second payments on account for 2024/25 are due by 31 July 2025
• Penalty charges apply for late filing and late payment without reasonable excuse
• Employers must issue P60 certificates to employees by 31 May 2025 covering the 2024/25 tax year

Essential facts about the UK tax year structure

When does tax year 2025/26 start and end?

The tax year 2025/26 commenced on 6 April 2025 and will conclude on 5 April 2026. This twelve-month period represents the fiscal window during which income earned will be assessed using the rates and allowances applicable to 2025/26. The beginning of a new tax year is a natural checkpoint for financial planning, as many allowances reset and become available for use.

For workers and businesses, the transition into the new tax year means that PAYE codes, pension contributions, and ISA subscriptions operate under updated parameters. The Bank of England Interest Rates can also influence financial planning decisions during this period, particularly for those with variable-rate debts or savings products.

Understanding the fiscal year calendar

Unlike calendar years, which run from January to December, the UK fiscal year spans April to April. This arrangement originated from historical tax collection practices and has been maintained to ensure continuity with the academic and business cycles that previously determined most economic activity in the country.

The 2025/26 tax year will cover all income received between 6 April 2025 and 5 April 2026. Individuals who receive employment income, self-employment profits, rental income, or investment returns during this period must include these in their 2025/26 Self Assessment return, due by 31 January 2027 if filing online.

What happens at the end of tax year 2026?

The tax year 2025/26 will end on 5 April 2026. At that point, the 2026/27 tax year will begin immediately on 6 April 2026. This cyclical pattern means that tax planning is an annual exercise, with each year bringing its own set of rates, thresholds, and deadlines that taxpayers must observe.

For those with specific financial obligations, marking these calendar dates in advance helps avoid the stress of missed deadlines. The end of the financial year also coincides with the academic year end and the start of the financial year for many businesses, making it a natural point for reviewing annual performance and planning the year ahead.

What are the key tax deadlines around the end of tax year 2025?

Several critical deadlines fall around the transition between tax years, and missing them can result in automatic penalties from HMRC. The dates apply differently depending on your filing method, the type of income you receive, and whether you are registering for the first time or submitting an annual return.

Self Assessment registration and filing deadlines

If you earned self-employment income or received property income during the 2024/25 tax year and have not previously registered for Self Assessment, you must do so by 5 October 2025. Late registration may result in HMRC imposing a deadline at their discretion, typically three months from the date they contact you about your obligations.

Paper tax returns for the 2024/25 tax year must reach HMRC by 31 October 2025, before 11:59pm. Online returns have a later deadline of 31 January 2026, though those who owe less than £3,000 and wish to pay through their PAYE tax code must submit by 30 December 2025.

Payments are also due at specific points. The second payment on account for 2024/25 was due by 31 July 2025, while the final balancing payment and first payment on account for the prior year must be settled by 31 January 2026.

Employer and third-party reporting obligations

Employers are required to provide P60 certificates to their employees by 31 May 2025, covering the tax year ended 5 April 2025. The P60 shows the employee’s total pay and the tax deducted throughout the year, which is necessary for completing Self Assessment returns accurately.

Additionally, employers and directors must submit P11D forms reporting benefits in kind provided to employees by 6 July 2025. These benefits, which may include company cars, private health insurance, or other perks, affect the employee’s tax position and must be declared to HMRC.

Value Added Tax considerations

Businesses registered for VAT must submit quarterly payments according to a schedule aligned to calendar quarters rather than tax years. The payment deadlines falling around this period include 7 May for the quarter ending in March, and 7 August for the quarter ending in June. Those on the flat rate scheme or annual accounting scheme should verify their specific obligations with HMRC.

What is the personal tax allowance for 2025/26?

At the time of writing, official figures for the personal tax allowance and income tax rates for the 2025/26 tax year have not been published by HMRC or confirmed through official government channels. Tax rates and allowances are typically announced during the Autumn Budget or Spring Statement and subsequently published on GOV.UK ahead of the new tax year.

The personal tax allowance determines how much income you can earn before paying Income Tax. The allowance has historically been subject to annual adjustments, and recent budgets have implemented freezes that affect the thresholds at which individuals begin paying higher rates of tax.

How personal allowance affects your tax code

Your tax code, which is used by employers to deduct the correct amount of tax from your pay, incorporates your personal allowance. Codes beginning with 1257L or similar indicate the standard personal allowance is being applied. Any changes to the allowance for 2025/26 will be reflected in codes issued before the new tax year begins or during the early months of the tax year.

Those who have overpaid or underpaid tax in previous years may find their codes adjusted to recover or repay the difference over time. Understanding how your tax code works can help you identify errors and ensure you are paying the correct amount. More information about tax codes is available through HMRC’s guidance on their official website.

What to expect for future tax years

Recent fiscal policy has seen the freezing of personal allowances and tax thresholds for multiple years, a measure designed to increase tax receipts without formally raising rates. Taxpayers should anticipate that the personal allowance for 2025/26 may remain at current levels or be subject to adjustment based on announcements in the Chancellor’s Budget statements.

For planning purposes, individuals should monitor official announcements and ensure their financial plans account for potential changes. The Household Support Fund June 2025 and related initiatives may provide context for broader government policy on financial support during periods of fiscal adjustment.

Important dates and deadlines in the tax year calendar

1. 6 April 2024: Tax year 2024/25 begins
2. 5 April 2025: Tax year 2024/25 ends
3. 31 May 2025: P60 certificates issued by employers for 2024/25
4. 6 July 2025: P11D forms due for benefits in kind during 2024/25
5. 31 July 2025: Second payment on account for 2024/25 due
6. 5 October 2025: Self Assessment registration deadline for new 2024/25 filers
7. 31 October 2025: Paper tax return deadline for 2024/25
8. 30 December 2025: Online return deadline for those paying via PAYE code
9. 6 April 2025: Tax year 2025/26 begins
10. 31 January 2026: Main online tax return and balancing payment deadline for 2024/25
11. 5 April 2026: Tax year 2025/26 ends
12. 6 April 2026: Tax year 2026/27 begins

This timeline demonstrates the overlapping nature of tax obligations, where reporting for one year extends well into the following year while new obligations simultaneously begin. Keeping accurate records throughout the year is essential for meeting these commitments without last-minute pressure.

What is confirmed and what remains unclear?

When reviewing tax information for the 2025/26 year, it is useful to distinguish between facts that are established and those that remain subject to confirmation. This clarity helps readers understand which information they can rely on immediately and which requires further verification.

This comparison highlights the importance of consulting official sources when making financial decisions that depend on confirmed figures. HMRC’s website remains the most reliable resource for up-to-date rates and allowance information as they are announced.

Why the end of the tax year matters for UK taxpayers

The end of the tax year represents more than an administrative deadline. It is a moment when individuals and businesses must account for income earned, report it accurately to HMRC, and ensure they have paid the correct amount of tax. Failing to do so can result in penalties, interest charges, and computational errors that may take years to resolve.

For many taxpayers, the tax year end is also an opportunity to make financial decisions that reduce future tax liabilities. Pension contributions, ISA subscriptions, and charitable donations made before the tax year ends can all provide relief that is calculated against the income of that specific year. Individuals approaching higher-rate thresholds may find that timing such decisions carefully produces meaningful savings.

The structure of the UK tax system, with its reset points and annual deadlines, means that regular review of financial affairs is practical and often rewarded. Those who engage with the process proactively tend to fare better than those who address tax obligations only when prompted by HMRC communications.

Sources and official guidance

The information in this article draws on guidance published by HM Revenue and Customs and the official GOV.UK website. The following resources provide authoritative information on Self Assessment obligations and tax year deadlines:

HMRC must receive your paper tax return by 11:59pm on 31 October 2025. If your return is late, you will be charged a penalty even if you have no tax to pay.

— GOV.UK, Self Assessment tax returns deadlines

The tax year in the UK runs from 6 April to the following 5 April. This applies to Income Tax, National Insurance contributions, and most other tax obligations.

— Low Income Tax Reform Group (LITRG)

For the latest official figures on personal allowances, tax rates, and band thresholds for the 2025/26 tax year, readers are encouraged to visit the official HMRC Self Assessment pages on GOV.UK. Official announcements during the Autumn Budget will clarify figures that remain pending confirmation.

Summary

The UK tax year 2024/25 concluded on 5 April 2025, with the new tax year 2025/26 beginning immediately the following day. Key deadlines for the 2024/25 reporting period include the paper return deadline of 31 October 2025, the online deadline of 31 January 2026, and the payment on account due date of 31 July 2025. Personal tax allowance and Income Tax rate figures for 2025/26 had not been confirmed by official sources at the time of writing, and taxpayers should verify these through GOV.UK following any Budget announcements.