Tax Code S1257N Explained
Scottish income tax rates apply. Your Personal Allowance is £12,579. You can earn up to this amount before paying income tax. You have transferred £1,260 of your Personal Allowance to your partner under Marriage Allowance. Your allowance is lower than the standard £12,570 because you transferred £1,260 to your partner.
Updated for the 2025/26 tax year (6 April 2025 to 5 April 2026).
Code breakdown
- Tax code
- S1257N
- Personal Allowance
- £12,579
- Region
- Scotland
- Suffix
- N
- Suffix meaning
- You have transferred £1,260 of your Personal Allowance to your partner under Marriage Allowance.
Example: £30,000 salary
Estimated take-home pay with tax code S1257N
- Gross salary
- £30,000
- Personal Allowance
- £12,579
- Taxable income
- £17,421
- Income tax
- -£3,495.44
- National Insurance
- -£1,394.4
- Annual take-home
- £25,110.16
- Monthly take-home
- £2,092.51
Why do I have tax code S1257N?
Common reasons HMRC may have issued this tax code:
- • You transferred £1,260 of your Personal Allowance to your partner
- • You applied for Marriage Allowance as the transferor
- • Your partner is a basic rate taxpayer and you earn under the Personal Allowance
Think your tax code is wrong?
If tax code S1257N does not match your circumstances, you may be paying too much or too little tax. You can:
- • Check your code in your Personal Tax Account on GOV.UK
- • Contact HMRC on 0300 200 3300 (Mon-Fri, 8am-6pm)
- • Use the HMRC app to view and update your tax code
How UK Tax Codes Work
Your tax code tells your employer or pension provider how much tax-free income you are entitled to in the current tax year. HMRC assigns your tax code based on your Personal Allowance, any taxable benefits, untaxed income, or adjustments from previous years. The numbers in your tax code represent your tax-free amount divided by 10, and the letters indicate your situation. For example, 1257L means a Personal Allowance of £12,570 with the standard suffix. If your code changes, your employer adjusts your tax deductions automatically. You can check and update your tax code through your Personal Tax Account on GOV.UK.
Tax codes are issued by HMRC at the start of each tax year and can change during the year if your circumstances change. Common reasons for a tax code change include starting a new job, receiving benefits in kind such as a company car, or having your Personal Allowance reduced because your income exceeds £100,000. If you have multiple jobs, each employer receives a separate tax code. Your primary employer normally receives your full Personal Allowance via a code like 1257L, while secondary employers typically receive a BR (basic rate) or D0 (higher rate) code meaning all income from that source is taxed at the relevant rate with no allowance.
If you live in Scotland, your tax code will start with an S prefix (for example S1257L), and if you live in Wales it will start with a C prefix (for example C1257L). These prefixes tell your employer to apply Scottish or Welsh income tax rates instead of the standard England and Northern Ireland rates. The Personal Allowance amount remains the same regardless of which country you live in within the UK.