Tax Year Dates & Deadlines in the UK

This guide is your one-stop resource for everything you need to know about UK tax year dates.

Understanding UK Tax Year Dates

The UK tax period is consistent every year and applies to all individual taxpayers. Here’s how it works:

• Start of the tax year: 6 April.
• End of the tax year: 5 April of the following year.

For example, the 2025 tax year will run from 6 April 2024 to 5 April 2025. Any income you earn, deductions you claim, or taxes you owe during this period will need to be reported in your tax return for that specific tax year.

2025 Tax Return Deadlines

HM Revenue and Customs (HMRC) provides two main ways to submit your tax return: by paper or online. Each method has different deadlines:

Paper Tax Returns:

Deadline: 31 October 2025

If you prefer to file a paper tax return, it must reach HMRC by midnight on this date. This method is less common now, as most people choose to file online, but it's still an option if you prefer.

Online Tax Returns:

Deadline: 31 January 2026

For most taxpayers, filing online is quicker and easier. The deadline for submitting your online tax return is midnight on 31 January 2026. This date is also the deadline for paying any tax you owe for the 2025 tax year.

Payments on Account:

First Payment Deadline: 31 January 2026

Second Payment Deadline: 31 July 2026

If you’re self-employed or have other forms of untaxed income, you will need to make payments on account for the next tax year. These are advance payments for your tax bill.

"In 2024, 11,246,962 returns were submitted online, making up 97.11% of the expected total after adjustments. Meanwhile, 335,000 paper tax returns were filed, accounting for 2.89% of the expected total after adjustments."

Why Meeting Tax Return Deadlines Matters

Missing tax return deadlines can result in fines, interest charges, and additional stress. Here’s what can happen if you fail to meet the key deadlines:

1. Late Filing Penalties:

If you miss the 31 October 2025 deadline for paper returns or the 31 January 2026 deadline for online returns, you will face an automatic penalty of £100, even if you don’t owe any tax.

If your return is more than three months late, you could face additional daily penalties of £10 per day (up to a maximum of £900). Further delays result in even larger penalties.

2. Interest on Late Payments:

If you miss the 31 January 2026 payment deadline, HMRC will charge interest on any pending amount. This interest accumulates until the full tax amount is paid, leading to a larger tax bill overall.

3. Increased Scrutiny from HMRC:

Consistently missing tax return deadlines can draw unwanted attention from HMRC, potentially leading to audits and investigations into your financial affairs.

Tips for Staying on Top of Your Tax Obligations

Mark Important Dates:

Note down key UK tax year dates and deadlines on your calendar. Setting reminders is another great way to stay on top of your obligations.

File Early:

Don’t wait until the last minute to file your tax return. Filing early gives you time to resolve any issues that may arise, and ensures that you’re not rushing at the deadline.

Keep Accurate Records:

Throughout the tax year, ensure accurate records of your income, expenses, and deductions. This will simplify the process when using UK tax return services and help avoid mistakes.

Use Online Filing:

Filing your tax return online is usually faster and more convenient. HMRC’s online system provides instant confirmation of receipt, and it calculates your tax liability automatically.

Look for Professional Advice:

If you have complex finances or are unsure about any aspect of your tax return, consider Taxd to ensure that you meet your obligations and take advantage of all available tax reliefs.

FAQs

1. What happens if I miss the tax return deadline?

Missing the deadline results in an automatic penalty of £100. If your return is more than three months late, additional daily penalties of £10 per day (up to £900) may apply. Further delays can lead to even larger fines.

2. Can I get an extension on the tax return deadline?

HMRC may grant an extension in exceptional cases, such as serious illness. However, you must contact HMRC as soon as possible to explain your situation. Extensions are not guaranteed, so it’s important to meet deadlines whenever possible.

3. What should I do if I make a mistake on my tax return?

If you realise you've made a mistake after filing, you can amend your tax return up to 12 months after the original filing deadline. For the 2025 tax year, you can make corrections until 31 January 2027.

5. How Taxd can help?

Our user-friendly software is designed to eliminate the need for accountants while offering valuable guidance on maximising your take-home pay. By identifying eligible allowances and clarifying your qualification status, we help pinpoint opportunities to potentially lower your tax liability.