Similarly, you might want to check you aren’t paying too little (in which case you’ll have to repay it).
It may look like a secret code, but the formula is pretty simple (and explained below). The most common HMRC tax code is 1257L, which is based on the Personal Tax Allowance of £12,570 – this is the amount you can earn before you need to pay tax.
Your tax code is used by your employer or pension provider to work out how much Income Tax to take from your pay or pension. HM Revenue and Customs (HMRC) will tell them which code to use.
How to check your tax code your tax code
You can find your tax code:
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If you check your tax code online or in the HMRC app, you can also:
- find your tax code for previous tax years
- sign up for paperless notifications – this means HMRC will email you when your tax code changes
Check what your tax code means
You can use the HMRC tax code checker to find out:
- what the numbers and letters in your tax code mean
- how much tax you will pay
- what you may need to do next
What the numbers mean in your HMRC tax code
The numbers in your tax code tell your employer or pension provider how much tax-free income you get in that tax year.
HMRC works out your individual number based on your Personal Allowance and income you have not paid tax on (such as untaxed interest or part-time earnings). They also consider the value of any perks you get from your employer (such as a company car).
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HMRC tax code letters and what they mean
The full list can be found on the GOV.UK website, but these are the most common, and what they mean:
- L – For an employee entitled to the standard tax-free Personal Allowance
- S – For an employee whose main home is in Scotland
- BR/ SBR – For a second job or pension
- M – For an employee whose spouse or civil partner has transferred some of their Personal Allowance (through Marriage Allowance)
- N – For an employee who has transferred some of their Personal Allowance to their spouse or civil partner (through Marriage Allowance)
- T – When HMRC needs to review some items with the employee
Recommended reading:
How to claim back tax with an HMRC tax rebate
If you think you are on the wrong tax code, you can contact HMRC on 0300 200 330 or speak to an advisor online via their live chat service.
HMRC will contact your employer to correct your tax code and you will get any money you overpaid in tax in your next payslip.
You can also claim back up to four additional years if you have been overpaying for some time.
