The letter T in a tax code

What T says

GOV.UK says the letter T means your tax code includes other calculations to work out your Personal Allowance.

GOV.UK's guidance for employers says that with a T code tax is deducted at the basic, higher and additional rates depending on the amount of taxable income, and that it is used when HMRC needs to review some items with the employee.

Letters in a tax code refer to your situation, and how it affects your tax-free Personal Allowance and the rates of tax you pay.

Reading the number with T

The number in front of T is read the same way as any other number in a code.

The numbers in your tax code tell your employer or pension provider how much tax-free income you get from them in that tax year.

GOV.UK's guidance for employers says you usually multiply the number in a tax code by 10 to get the total amount of income that can be earned before being taxed. Its example: with the code 1257L, an employee can earn £12,570 before being taxed.

To work out your individual number, HMRC starts with your tax-free Personal Allowance and takes off any income you have not paid tax on (such as untaxed interest or part-time earnings) and any other deductions in your tax code (such as company benefits or the High Income Child Benefit Charge). It then replaces the final digit with a letter.

The standard allowance for comparison

The standard Personal Allowance is £12,570, which is the amount of income you do not have to pay tax on.

GOV.UK's example: the standard Personal Allowance of £12,570 less a £1,570 medical insurance benefit from an employer leaves a tax-free amount of £11,000, which makes the code 1100L.

The Personal Allowance goes down by £1 for every £2 that your adjusted net income is above £100,000, so it is zero if your income is £125,140 or above. You do not get a Personal Allowance on taxable income over £125,140.

GOV.UK says you may be able to earn more before you start paying Income Tax if you claim Blind Person's Allowance, and that this tax-free allowance is added to your Personal Allowance.

How T differs from L, M and N

GOV.UK's guidance for employers says that with L, M and N, tax is deducted at the basic, higher and additional rates depending on the amount of taxable income: L for an employee entitled to the standard tax-free Personal Allowance, M where a spouse or civil partner has transferred some of their Personal Allowance, and N where the employee has transferred some of theirs to a spouse or civil partner.

GOV.UK says the letter L means you are entitled to the standard tax-free Personal Allowance.

GOV.UK says the letter M is about Marriage Allowance: you have received a transfer of 10% of your partner's Personal Allowance.

GOV.UK says the letter N is about Marriage Allowance: you have transferred 10% of your Personal Allowance to your partner.

• Letter LThe letter L and the allowance it stands for
• Letter MMarriage Allowance received
• Letter NMarriage Allowance transferred

Checking a code for yourself

GOV.UK says you can find your tax code by checking it online (you need to sign in or create an online account), in the HMRC app, on your payslip, or on a Tax Code Notice letter from HMRC if you get one.

GOV.UK's Check your Income Tax service lets you check your tax code and Personal Allowance, see your estimated income from jobs and pensions and the tax you can expect to pay for the current tax year, update details of your income, see if your tax code has changed, tell HMRC about changes that affect your tax code, and update your employer or pension provider details.

GOV.UK has a tool for checking what a tax code means: it explains what the numbers and letters mean, how much Income Tax you are due to pay, and how to update your records if something is wrong. To use GOV.UK's tax code checker you need your tax code, your annual income before any deductions, your company benefits details and your State Pension amount.

Why a code changes

HMRC changes your tax code if you need to pay a different amount of tax. GOV.UK says this usually happens when your income or circumstances change, for example if you start a new job, get taxable state benefits, start to get income from an additional job or pension, earn savings interest above your Personal Savings Allowance, or your weekly State Pension amount changes.

HMRC will usually contact you to explain how it worked out your individual tax code if your tax code changes.

If the code looks wrong

HMRC usually updates your tax code using information it gets from your employer or pension provider. GOV.UK says that if your tax code is wrong, it is usually because HMRC has incorrect or missing information, and that to correct it you check and update the details HMRC has about you.

GOV.UK says using the online service is the quickest way to check and update your details: sign in to the Check your Income Tax online service, check your employment, pension, estimated taxable income, company benefit and expenses details, and update your details if there is anything wrong or missing.

If you think your tax code is wrong and you cannot use the online service, GOV.UK says you can contact HMRC. HMRC's Income Tax enquiries line is 0300 200 3300. The Income Tax enquiries line is open Monday to Friday, 8am to 6pm, and closed on bank holidays.

• Tax code notice (P2)The letter HMRC sends when your code changes

GOV.UK pages on this

• GOV.UK: What your tax code meansGOV.UK's page on what your tax code means: the numbers, the letters and a worked example.
• GOV.UK: Check what your tax code meansGOV.UK's tax code checker, which explains the letters and numbers in a code.
• GOV.UK: Check your Income TaxGOV.UK's Check your Income Tax service for the current year, where you can see your tax code and Personal Allowance.

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