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P45 Box 6 — Tax code at leaving date — Tax code, with or without Week 1/Month 1 marker

Your PAYE tax code as at your last day. If followed by W1 or M1, it's non-cumulative — the new employer should not apply earlier pay/tax to your new employment.

At a glance

Entry
Tax code, with or without Week 1/Month 1 marker
Feeds to
Your new employer's payroll — they use this code until HMRC issues an update. If W1/M1, the new employer's PAYE is non-cumulative until reconciled.
Check against
The tax code on your last payslip from the old employer.

What this means

Box 6 shows the tax code your old employer applied to your final pay period. Standard codes (1257L, K475, D0, BR, S1257L) are cumulative — the new employer starts PAYE using them plus the Part 1A YTD figures.

If the code is followed by W1 (weekly-paid) or M1 (monthly-paid), the code is non-cumulative. The new employer should NOT incorporate your earlier pay and tax — they treat your new employment as fresh for PAYE purposes. This usually signals a mid-year HMRC-issued code that bypassed cumulative correction; HMRC will reconcile at year-end.

Implications for your tax

  • Determines your first-paycheck tax at the new employer. A cumulative code with YTD figures from Part 1A = smooth transition. A W1/M1 code = potential over- or under-deduction until HMRC updates.
  • A K code in Box 6 means your benefits in kind or tax underpayment exceeds your allowance — the new employer must apply negative allowance.
  • If BR, the new employer taxes at 20% on every pound (no allowance). Common when you didn't hand over a P45 or it was your second job at the old employer.

Common pitfalls

  • The W1/M1 suffix is easy to miss on the P45 — look carefully. It significantly changes how the new employer calculates PAYE.
  • If the code looks wrong (e.g., BR when you only had one job), ask HMRC for your correct code via personal tax account before starting the new job — saves a refund claim later.

For 2025-26 (tax year 6 April to 5 April)

Standard tax code
1257L (England / Wales / NI) · S1257L (Scotland) · C1257L (Wales)
The numeric part is your personal allowance ÷ 10 (£12,570 ÷ 10 = 1257). The L suffix indicates the standard code with no adjustments.
Personal Allowance
£12,570
Tapered away above £100,000 adjusted net income (loses £1 for every £2 over). Additional-rate threshold frozen at £125,140 under §8 ITA.

Values sourced from central tax-year config at build time — update automatically on FY rollover.

Related P45 entries

Reconciling your pay? Use the take-home pay calculator to verify PAYE and NI on any salary for 2025/26 or 2026/27, and the tax code checker to decode your final tax code.

Sources

P45 structure per HMRC PAYE forms guidance. Thresholds and rates current for 2025/26 (tax year 6 April 2025 to 5 April 2026); 2026/27 figures included where published.

Related Calculators

Last updated 21 June 2026Tax year 2025-26

Data sources: HMRC (gov.uk/hmrc)

This tool is general information only, not financial advice.

Reviewed by UK Tax Tools Editorial Desk

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