Taking a second job, or juggling two part-time roles? Tax with two employments works differently: your personal allowance sits with one job (or is split by HMRC), National Insurance is calculated separately for each employer, and student loan is due on the combined total. This calculator shows the per-job and combined take-home — and flags any tax that PAYE will get wrong in-year.
6 min read·Updated 2026-07-18·🇬🇧 UK
Calculator
Your Two Jobs
£
£
Scottish taxpayer
Tax Codes
Allowance on Job 1
Split codes
Deductions
None
Sacrifice
Relief
Per-job & combined take-home
Combined income, split
Your result
Enter both salaries above to see your personalised result.
Key Takeaways
There is no special "second job tax rate" — your Personal Allowance sits on the main job (1257L) and the second job is taxed at basic rate (BR), or D0 if the main job uses up the basic band. National Insurance is charged per job, so each employment gets its own £12,570 threshold — two part-time jobs often pay less NI than one job of the same total. Bands apply to your combined income, so a second job can tip you into the 40% band and leave a BR code under-collecting, which HMRC reconciles later. Total tax depends only on total income.
How it works
How is a second job taxed in the UK?
Your Personal Allowance goes on the main job while the second is taxed at basic rate — but the three systems interact differently, and they follow different rules:
Income tax is annual and personal — your bands apply to total income. PAYE approximates this by giving your allowance to the main job (1257L) and taxing the second at basic rate (BR). If your combined income crosses £50,270, a BR code under-collects and HMRC will reconcile later.
National Insurance is per employment. Each job gets its own £12,570 primary threshold, which is why two part-time jobs often attract less NI than one job paying the same total.
Student loan is due on total income, but each employer applies the threshold separately in payroll — Self Assessment trues it up.
What is the take-home on a £30,000 job plus a £10,000 second job?
Job 1 (1257L): tax (£30,000 − £12,570) × 20% = £3,486; NI £1,394.40 → take-home £25,120. Job 2 (BR): tax £10,000 × 20% = £2,000; NI on (£10,000 − £12,570) = nothing → take-home £8,000. Combined take-home: £33,120 on £40,000 gross — an 82.8% keep rate, £800 a year better than a single £40,000 job (£32,320) because the second employment gets its own NI threshold, sheltering the whole £10,000 from National Insurance.
Your personal allowance is normally attached to your main job through your tax code (1257L), while the second job is taxed at basic rate from the first pound with a BR code — or D0 if your main job already uses up the basic band. There is no separate 'second job tax rate'; your total annual tax depends only on your total income.
Do I pay more National Insurance with two jobs?
Often you pay less than you would on the same total from one job. NI is charged per employment, so each job gets its own £12,570 threshold. Two jobs of £15,000 each attract NI on just £2,430 per job, whereas one £30,000 job pays NI on £17,430. This calculator computes NI separately for each employment, exactly as payroll does.
Can I split my personal allowance between two jobs?
Yes — if neither job alone uses your full £12,570 allowance you can ask HMRC to split it, for example 800L on one job and 457L on the other. Use the split-codes mode in this calculator to model any division and see whether it stops tax being over-deducted in-year.
How do student loans work with two jobs?
Through payroll, each employer applies the threshold separately, so if each job individually sits below your plan's threshold nothing is deducted — but HMRC can collect the correct amount based on total income through Self Assessment. This calculator shows the liability on your combined income so you know the true annual position.
Will a second job push me into a higher tax band?
It can. Bands apply to your total income, so if your main job pays £45,000 and a second job adds £10,000, the top £4,730 falls into the 40% band even though each job alone is below £50,270. The calculator warns you when your BR-coded second job is under-taxed so an HMRC bill doesn't surprise you.
Is it worth taking a second job after tax?
Usually yes, but the marginal maths matter: a basic-rate taxpayer keeps 72–80% of second-job earnings (tax plus NI above the per-job threshold), while someone near £50,270 keeps as little as 58%. Enter both salaries and compare the combined take-home against your single-job baseline to see the real gain.
Disclaimer: Figures are estimates based on current rates and rules; in-year PAYE deductions depend on the codes HMRC issues. Verify with GOV.UK or consult a qualified accountant before making financial decisions based on these figures.