UK Tax Codes Explained

The most common UK tax code for 2026/27. The number 1257 represents your tax-free personal allowance of £12,570 (multiply by 10). The letter L confirms you are entitled to the standard personal allowance with no adjustments.

Your personal allowance is £12,570 but tax is calculated on a non-cumulative basis — each pay period is treated independently. This is a temporary emergency measure, often applied when starting a new job without a P45. It should resolve within a few payslips once HMRC updates your record.

Identical to W1 but for monthly-paid employees. Your personal allowance is £12,570 but each month is calculated independently without reference to previous months. Contact HMRC if this persists beyond your first 2-3 payslips.

All income from this employment is taxed at 20% with no personal allowance. Commonly used for second jobs where your allowance is already allocated to your primary employment. If this is your only job, it is likely incorrect — contact HMRC on 0300 200 3300.

All income from this source is taxed at 40%. Typically applied to a second job or additional income where your basic rate band has already been used by your primary employment.

All income from this employment is taxed at 45%. Applies to individuals earning over £125,140 per year where both personal allowance and basic/higher rate bands are consumed by primary employment.

No income tax is deducted. Rare — typically applies to diplomats, certain offshore workers, or individuals whose total income falls below the personal allowance across all sources.

You have no tax-free allowance. All income is taxed using standard rate bands (20%, 40%, 45%). Often used when HMRC lacks information to assign a proper code, or when your allowance is fully consumed by benefits in kind.

The most aggressive emergency code. No personal allowance and non-cumulative calculation. You are taxed on all earnings each period independently. This typically resolves once HMRC processes your details.

The S prefix indicates you are a Scottish taxpayer. Your personal allowance is still £12,570 but you pay Scottish income tax rates (19% starter, 20% basic, 21% intermediate, 42% higher, 47% top rate) instead of UK-wide rates.

All income from this employment is taxed at the Scottish basic rate of 20% with no personal allowance. Used for second jobs of Scottish taxpayers.

All income from this source is taxed at the Scottish intermediate rate of 21%. Used for second jobs where the starter and basic bands are consumed.

All income from this employment is taxed at the Scottish higher rate of 42%. Used for secondary income of higher-rate Scottish taxpayers.

All income from this employment is taxed at the Scottish top rate of 47%. Applies to Scottish taxpayers earning above £125,140 on secondary income.

The C prefix identifies you as a Welsh taxpayer. Currently Welsh rates are the same as England/NI rates, so the practical effect is identical to 1257L. The prefix exists for administrative tracking by HMRC.

All income taxed at Welsh basic rate of 20% with no personal allowance. Used for second jobs of Welsh taxpayers. Currently identical in effect to BR.

All income from this employment taxed at Welsh higher rate of 40%. Currently identical in effect to D0.

All income from this employment taxed at Welsh additional rate of 45%. Currently identical in effect to D1.

K codes mean your untaxed income (company benefits, state pension, etc.) exceeds your personal allowance. The number after K represents the amount to ADD to your taxable pay (multiply by 10). For example, K475 means £4,750 is added to your taxable income. Your employer cannot deduct more than 50% of your gross pay through a K code.

Your personal allowance has been reduced to £11,850, typically because you receive a taxable benefit (like a company car or private medical insurance) that reduces your tax-free amount. The difference from 1257L (£720) represents the annual value of benefits being taxed through your code.

Your personal allowance is reduced to £11,000. This means £1,570 of benefits or underpaid tax from a previous year is being collected through your tax code. Check your HMRC tax code notice to understand what adjustments have been made.

You are receiving the Marriage Allowance transfer from your spouse or civil partner. Your personal allowance is increased by £1,260 (10% of the standard allowance) to £13,830. Your partner must have transferred their allowance to you via HMRC.

The M suffix confirms you are receiving the Marriage Allowance from your partner. Your effective allowance is £13,830 (£12,570 + £1,260). This is equivalent to code 1383L.

The N suffix means you have transferred 10% of your personal allowance (£1,260) to your spouse or civil partner. Your effective allowance is reduced to £11,310. This benefits couples where one partner is a non-taxpayer.

The T suffix means your tax code includes items that HMRC needs to review. Your allowance is still £12,570 but there are complexities in your tax affairs. HMRC will not automatically update this code — they will write to you if changes are needed.

The X suffix (equivalent to W1/M1) means your tax is calculated on a non-cumulative basis. Each pay period is treated independently. This is temporary and should resolve once HMRC processes your details.

K100 means you have untaxed income (benefits, state pension, underpayments) worth £1,000 more than your personal allowance. This amount is added to your taxable pay. Your employer cannot deduct more than 50% of your gross pay through a K code.

K475 means you have untaxed income (benefits, state pension, underpayments) worth £4,750 more than your personal allowance. This amount is added to your taxable pay. Your employer cannot deduct more than 50% of your gross pay through a K code.

K800 means you have untaxed income (benefits, state pension, underpayments) worth £8,000 more than your personal allowance. This amount is added to your taxable pay. Your employer cannot deduct more than 50% of your gross pay through a K code.