Check If You're Paying the Right Amount of Tax

Making sure you're paying the correct amount of Income Tax helps you avoid overpaying or building up unexpected tax bills. Whether you're employed, receive a pension, or have other sources of income, HMRC provides free online tools to check your tax code, review your payments, and update your details if something's wrong.

Understanding your tax code

Your tax code is a combination of numbers and letters that tells your employer or pension provider how much Income Tax to deduct from your pay. If your tax code is wrong, you could be paying too much or too little tax.

You can find your current tax code on your payslip. To check whether it's correct, sign in to the 'check your Income Tax' service on GOV.UK or use the HMRC app. This service covers the current tax year (6 April 2025 to 5 April 2026) and lets you:

• Check your tax code and Personal Allowance
• See your estimated income from jobs and pensions
• View the tax you can expect to pay for the current tax year
• Tell HMRC about changes that affect your tax code
• Update your employer or pension provider details

Note that you cannot use this service if you pay all your Income Tax through Self Assessment.

Checking if your payslip is correct

Every time you're paid, your employer should give you a payslip showing:

• Your tax code
• Your 'gross' pay (the total before deductions)
• Any 'deductions' (money taken off, such as tax, National Insurance, pension contributions or student loans)
• Your 'net' pay (the amount you receive after deductions)

To verify the tax is correct, first compare the tax code on your payslip with the one HMRC has for you in the online service or app. If they're different, speak to your employer.

If the tax codes match, check what your tax code means using the online service, the HMRC app, or the 'understand your tax code' guidance on GOV.UK. Make sure the tax code suits your income and circumstances. If it doesn't match your situation, you might be on the wrong tax code and should update it.

If your tax code appears correct, use the 'estimate your tax for the current year' tool on GOV.UK. Enter your gross pay and tax code from your payslip, then compare the result to the actual tax shown on your payslip. If they're the same, your tax is likely correct. If they're different, speak to your employer.

Reviewing your annual tax summary

Once HMRC calculates everyone's Income Tax (between June and November each year), you can check how much you paid during the previous tax year. For 2024/25 (6 April 2024 to 5 April 2025), use the 'check how much Income Tax you paid last year' service.

You cannot use this service if you paid any of your Income Tax through Self Assessment.

You may also be able to use this service to get a tax refund or pay tax you owe. You'll need a tax calculation letter (known as a 'P800') that confirms you can do this online.

To access either the current year or previous year service, you'll need to sign in using Government Gateway details. If you don't have these, you can create them. You may be asked to prove your identity using photo ID like a passport or driving licence to keep your details safe.

Working out if you should be paying tax

To determine whether you should be paying Income Tax at all:

1. Add up all your taxable income, including taxable state benefits

2. Work out your tax-free allowances (most people get a Personal Allowance of tax-free income)

3. Take your tax-free allowances away from your taxable income

If there's anything left, you're a taxpayer. If there's nothing left, you should not be paying tax and may be due a refund.

You pay tax on income including:

• Money you earn from employment
• Profits from self-employment (above the first £1,000 trading allowance)
• Most state benefits (such as State Pension, Jobseeker's Allowance, and Carer's Allowance)
• Most pensions
• Rental income (above the first £1,000 property allowance, unless you're using the Rent a Room Scheme)
• Job benefits
• Interest on savings over your savings allowance

You don't pay tax on income from ISAs, Premium Bond wins, National Lottery prizes, dividends under your dividend allowance, or most state benefits like Universal Credit, Personal Independence Payment, and Disability Living Allowance.

If you cannot use the online services

If you're unable to create a personal tax account, contact HMRC for advice. You can also estimate how much Income Tax you should pay without signing in using the estimation tools on GOV.UK.

For Self Assessment taxpayers, there's a different process to change a tax return.

What to do if your tax is wrong

If you discover you're paying too much tax, you may be due a refund. If you're paying too little, you'll need to pay what you owe. The online service may allow you to sort this out directly if you have a P800 letter confirming you can do so.

If your tax code is wrong, update it through the online service or contact HMRC. If your employer is using the wrong tax code, speak to them first.

For more complex situations or if you need help checking your tax, contact HMRC or speak to an accountant.

Sources

• Check your Income Tax for the current year
• Check how much Income Tax you paid last year
• Check if the tax on your payslip is correct
• Check what your tax code means
• Income Tax: introduction

This article provides general guidance based on current HMRC rules. For advice specific to your situation, speak to your accountant.