Tax code calculators
Check my tax code: am I on the right one?
Independent site, not HMRC. Only HMRC can change your code: use your HMRC online account or app.
Your incomes and allowances on one side, the code on your payslip on the other: the code they point to and the gap over the year.
Your situation points to
1257L
Your current code takes about the right tax for the year.
| Tax due for the year | £4,286.00 |
| Taken with 1257L | £4,284.00 |
| Taken with the expected code | £4,284.00 |
| Personal Allowance | £12,570 |
Estimate on employment and pension income only. HMRC sets your code from its own records; savings, property and other income can change it.
Your tax code is right when it collects, over the year, the tax due on everything HMRC taxes through your pay. That starts from the Personal Allowance of £12,570 for 2026 to 2027, reduced above £100,000 of income, raised or lowered by £1,260 of Marriage Allowance, lowered by company benefits and the State Pension, and raised by job expenses. A second job or pension gets no allowance of its own: BR, or D0 when your main pay is already in the higher rate band. Take £26,000 from a main job and £9,000 from a second: the tax due is £4,486.00. With 1257L and BR, payroll takes £4,484.00; with 1257L on both jobs it takes only £2,684.00, and the shortfall comes back as a bill or a lower code next year. The checker above makes this comparison for your figures and gives the code they point to.
Codes for two jobs
Expected codes
1257L + BR
| Tax due for the year | £4,486.00 |
| Second job with 1257L by mistake | £0.00 |
| Second job with its expected code | £1,800.00 |
Rules read on HMRC’s texts by Radif Partners · Editorial policy · Method
What the checker compares
It does two calculations. The first is the tax due for the year on your employment and pension income, with the allowances and rates that apply to you in 2026 to 2027 (Income Tax rates and allowances). The second is the tax your current codes take over the year with HMRC's payroll method, from the month the job started. The gap between the two is what you would be over- or undercharged by 5 April if nothing changed. It also builds the code your figures point to, the way HMRC describes it: the allowance, minus what is taxed through the code, plus what gives relief, with the last digit dropped (what your tax code means).
| Situation | Code it points to |
|---|---|
| One job, nothing else | 1257L |
| Company medical insurance worth £1,570 | 1100L |
| Marriage Allowance received | 1383M |
| Two jobs, £26,000 and £9,000 | 1257L and BR |
| Workplace pension £9,000 and full State Pension | 2L |
| Income of £110,000 | 757L |
| Job expenses of £600 | 1317L |
The usual reasons a code is off
Most gaps come from information HMRC did not have or has not updated. A second job coded 1257L as well as the first gives two allowances, so too little tax is taken. A main job coded BR after a change of employer takes too much. A company car handed back, a State Pension counted at the wrong weekly rate, or Marriage Allowance claimed but not yet in the code all shift the number. When you start a job without a P45, an emergency code can run for a few months before the right one arrives.
Two codes on the same pay
BR against 1257L, over the year
+£2,516.00
| Tax with 1257L | £2,284.00 |
| Tax with BR | £4,800.00 |
| Each month | £209.67 |
Pensioners, Scotland and Wales
If you receive the State Pension, enter its weekly amount: it is paid without tax taken off, so HMRC usually collects its tax through the code on a workplace pension or a job, which lowers that code sharply (how your State Pension is taxed). With the full new State Pension of £241.30 a week, almost all of the allowance goes. Choose Scotland or Wales if you live there: the checker then gives an S or C code and uses the Scottish or Welsh rates. Marriage Allowance only works one way per couple: the partner who receives it gets an M code, the one who gives it an N code (Marriage Allowance).
Putting it right with HMRC
Only HMRC can change your code. Sign in to the Check your Income Tax service or the HMRC app, check each employment, pension, benefit and expense, and update anything that is wrong or missing; that is the quickest route according to GOV.UK. HMRC then tells you and your employer the new code within 15 working days. A monthly payroll should use it on the next or the following payslip, a weekly payroll on the third. If you started a new job, wait 35 days for HMRC to receive the income details before contacting it.
When the new code is cumulative and you have paid too much, the difference comes back on the payslip that first uses it. The refund page covers the cases where it does not, and the underpaid tax page what happens when you owe.