UK Tax Year Explained: Key Dates and Deadlines for 2024/25

JK

John Kyprianou

Director, IAK Accountants

Introduction

Understanding the UK tax year is crucial for both individuals and businesses. Missing key deadlines can result in penalties and interest charges from HMRC. This guide breaks down everything you need to know about the tax year in simple terms, helping you stay compliant and avoid unnecessary costs.

The UK tax year runs from 6 April to 5 April the following year - a unique system that dates back centuries. Let's explore what this means for you and your business.

What is the UK Tax Year?

The UK tax year, also known as the 'fiscal year' for individuals, runs from 6 April to 5 April. For example:

  • 2024/25 tax year: 6 April 2024 to 5 April 2025
  • 2025/26 tax year: 6 April 2025 to 5 April 2026

This period determines which year your income and expenses fall into for tax purposes. It's different from the calendar year and can be confusing for those new to UK tax.

Key Tax Deadlines You Can't Miss

Self Assessment Deadlines

If you're self-employed or have additional income, these dates are critical:

  • 31 October: Paper tax return deadline
  • 31 January: Online tax return deadline and payment deadline
  • 31 July: Second payment on account deadline

Missing the 31 January deadline results in:

  • £100 automatic penalty
  • Additional penalties if delays continue
  • Interest on unpaid tax

PAYE Deadlines for Employers

Running payroll? Mark these dates:

  • 19th of each month: PAYE payment deadline (22nd if paying electronically)
  • 6 April: Year-end submissions due
  • 31 May: P60s must be given to employees
  • 6 July: P11D forms deadline for benefits in kind

Corporation Tax Deadlines

Limited companies have different deadlines based on their accounting period:

  • 9 months and 1 day after accounting period ends: Corporation tax payment due
  • 12 months after accounting period ends: Corporation tax return deadline

Tax Planning Throughout the Year

Before 5 April

The end of the tax year is crucial for tax planning. Consider:

  • Pension contributions: Maximise your annual allowance (currently £60,000)
  • ISA contributions: Use your £20,000 ISA allowance
  • Capital gains: Time asset disposals to manage your tax bill
  • Charitable donations: Make Gift Aid donations before year-end

After 6 April

The new tax year brings opportunities:

  • Fresh ISA and pension allowances
  • New dividend allowance (£1,000 for 2024/25)
  • Updated tax bands and rates
  • Time to implement tax-efficient strategies

Common Tax Year Mistakes to Avoid

We see these errors regularly at IAK Accountants:

  1. Confusing tax years with calendar years - Always use the 6 April to 5 April dates
  2. Missing the 31 January deadline - Set reminders well in advance
  3. Forgetting payments on account - Budget for July payments too
  4. Not keeping proper records - HMRC can request records from the last 6 years

Digital Tax Requirements

Since April 2022, all VAT-registered businesses must follow Making Tax Digital (MTD) rules. This means:

  • Using compatible software for VAT records
  • Submitting VAT returns digitally
  • Keeping digital links between systems

Learn more about our Xero accounting services to ensure MTD compliance.

How IAK Accountants Can Help

Managing tax deadlines and compliance can be overwhelming, especially when running a business. Our team provides:

  • Year-round tax planning to minimise your liability legally
  • Deadline management so you never miss important dates
  • Digital bookkeeping through modern cloud software
  • Expert advice on complex tax matters

We work with businesses across North London, helping them navigate the UK tax system efficiently.

Stay Ahead of Tax Deadlines

Don't let tax deadlines catch you off guard. Proper planning throughout the year can save you money and stress. Whether you need help with self assessment, corporation tax, or general tax planning, our experienced team is here to help.

For more information about staying compliant with UK tax requirements, visit GOV.UK's tax guidance or contact our team for personalised advice tailored to your situation.

About the Author

JK

John Kyprianou

Director at IAK Accountants with over 11 years of experience in accounting and business advisory. John specialises in helping UK businesses navigate complex tax regulations, optimise their financial structures, and achieve sustainable growth. His expertise spans corporate tax planning, international business structuring, and strategic financial consulting.