How is a Second Job Taxed in the UK?
When you work two jobs in the UK, HMRC applies your full £12,570 Personal Allowance against your primary (main) employer income. Your second job is then taxed from the first pound it pays you, using an emergency or flat-rate tax code — typically BR (Basic Rate, 20%) or D0 (Higher Rate, 40%) depending on your total combined income. For a single job calculation, you can use our standard income tax calculator.
Tax Codes for Second Jobs
HMRC assigns your second employer one of these tax codes: BR means all income taxed at Basic Rate (20%), D0 means all income taxed at Higher Rate (40%), and D1 means all income taxed at Additional Rate (45%). The exact code depends on whether your combined income exceeds £50,270 or £125,140.
National Insurance on Two Jobs
National Insurance Class 1 is calculated independently by each employer — each applies their own Primary Threshold (£12,570/year) based on standard Class 1 National Insurance rates. This means you effectively pay NI from the first pound at each job. However, if your total NI contributions exceed the maximum for the year, HMRC will refund the overpayment.
Self Assessment
If your second job income exceeds £1,000 in a tax year, you must register for and submit a Self Assessment tax return. HMRC uses this to reconcile your true tax liability across both income sources and issue any refunds or additional bills. If you want to know how much extra you need to earn to hit a specific take-home goal, consider working out your required salary instead.
Two Jobs Tax FAQs
How is a second job taxed in the UK?
Your Personal Allowance (£12,570) is normally applied to your main job. Your second job income is therefore taxed from the very first pound — typically at 20% Basic Rate (BR tax code) unless you earn enough from your first job to push you into the 40% Higher Rate band.
Can I split my Personal Allowance between two jobs?
Yes. You can contact HMRC to split your £12,570 Personal Allowance between two employers, which can reduce the tax you pay on your second job. HMRC will adjust each employer's tax code accordingly.
Do I pay National Insurance on both jobs?
Yes, Class 1 National Insurance is calculated independently by each employer based on what they pay you. If your combined earnings push you over £50,270, you may overpay NI — but HMRC will refund this after year-end.
