Tax Code · 2026/27
T Tax Code Suffix: Special Items in Your Tax Calculation
T suffix means HMRC has used "other calculation items" when working out your tax code - typically items that need annual review or that HMRC considers confidential. The numeric portion still represents your annual tax-free amount.
What the T suffix tax code means
T after the numbers (e.g. 1257T, 819T, 600T) indicates HMRC has used special items in computing the code - rather than the standard PA + benefit-in-kind / underpayment adjustment. Common triggers: marriage allowance recipient, child benefit clawback adjustment, items requiring annual review.
The numeric portion behaves identically to an L code - it is your annual tax-free amount (numeric × 10 = £ tax-free, so 819T = £8,190 PA after deductions).
T codes are functionally identical to L codes from PAYE's perspective. The suffix tells HMRC internal systems to flag the case for annual review rather than auto-adjusting.
When you'll see T suffix
- You receive Marriage Allowance from your spouse (the recipient gets a T-suffix to indicate the transfer requires annual confirmation).
- You have a High Income Child Benefit Charge (HICBC) adjustment built into your code (£X reduction in PA equivalent to expected HICBC charge for the year).
- You have a substantial benefit-in-kind that HMRC reviews annually (company car at certain CO2 bands, accommodation BIK).
- You requested HMRC keep your tax-code calculation private from your employer (T is sometimes used as a privacy flag).
What to do if you have a T suffix code
- Verify the calculation: log in to Personal Tax Account → Tax Code section → "How we calculated your tax code". The breakdown explains every adjustment.
- If the T suffix is unexpected or the numeric portion seems wrong: call HMRC on 0300 200 3300. Have your latest tax-code notice (P2) to hand.
- Marriage Allowance T codes: re-confirm via gov.uk/marriage-allowance if your spouse's circumstances changed (income above £12,570 means they no longer qualify to transfer).
- HICBC T codes: if your adjusted net income will be different from HMRC's assumption, request a code adjustment via Personal Tax Account.
Worked example
Marriage Allowance recipients are coded with M suffix (e.g. 1383M), not T. T is reserved for codes containing items HMRC needs to review annually (HICBC adjustment, large BIK at certain CO2 bands, complex private items). Example T case: a £75,000 earner with £2,000 of HICBC built into the code would carry a T suffix with reduced numeric portion reflecting the adjustment.
Want to see the numbers for your own salary? Use the salary calculator and pick 2026/27 to see how T suffix interacts with your full take-home.
Frequently asked questions about T suffix
- Is a T code worse than an L code?
- No - functionally identical from a PAYE calculation standpoint. T just flags the code for annual HMRC review (typically before the next tax year). The numeric portion is your tax-free amount in £ × 10.
- Why has my code changed from L to T?
- Most common reasons: HMRC built in a HICBC adjustment, you have a new BIK item HMRC reviews annually, or you have complex private items flagged for annual review. Note: Marriage Allowance recipients get M suffix (not T) - the T suffix is specifically for annually-reviewed items. Personal Tax Account shows the underlying calculation - read the "how we calculated your tax code" breakdown.
- Does T mean I will owe tax at year-end?
- Not necessarily. T just indicates special items in the calculation, not a likely underpayment. The numeric portion is HMRC's best estimate of your tax-free amount for the year - if it accurately reflects your circumstances, no year-end adjustment is needed.
- Can I switch from T back to L?
- Sometimes. If the special items disappear (e.g. Marriage Allowance withdrawn, BIK ended, HICBC no longer applicable), HMRC will issue a new code with L suffix and updated numeric portion. The change happens automatically when HMRC processes the relevant trigger (P11D, marriage allowance withdrawal, etc.).
Related tax codes
- 1257L
1257L is the default UK tax code for 2026/27. It gives you the full £12,570 Personal Allowance before Income Tax is deducted - the number 1257 is your allowance divided by 10, and the L means a standard untouched allowance.
- K
A K-prefix tax code (e.g. K475) means your taxable deductions exceed your Personal Allowance. The number represents extra taxable income added to your pay, not a tax-free amount.
- BR
BR stands for 'Basic Rate'. It taxes 100% of pay from that source at 20%, with no Personal Allowance. HMRC uses it most often on second jobs and pensions, where your £12,570 PA is already used up by the main income.
- 1257L W1/M1/X
An 'emergency' tax code is a non-cumulative version of your main code. You'll see W1 (weekly), M1 (monthly), or X (either) appended - each pay period is taxed in isolation, which usually means you pay more tax than you owe.
Sources & further reading
All figures and definitions on this page reflect the 2026/27 UK tax year and are cross-checked against HMRC guidance.
- HMRC — What your tax code means (official meanings for L, BR, D0, D1, K, 0T, NT, M, N, S, C, T)
- HMRC — Income Tax rates and Personal Allowance (2026/27 bands and thresholds)
- HMRC — Emergency tax codes (W1, M1 and X suffixes)
- HMRC — Rates and thresholds for employers 2026 to 2027
- HMRC — Your Personal Tax Account (check your current code and how it was calculated)
- Our methodology & calculation sources →