UK Two-Jobs Tax Calculator 2026/27

How HMRC taxes two employments in 2026/27

When you have two PAYE employments at the same time, each employer deducts Income Tax and National Insurance using the tax code HMRC issues for that job. Income Tax is worked out on your COMBINED earnings, but NI is calculated PER EMPLOYMENT - which can save or cost money.

Income Tax across two jobs

The £12,570 Personal Allowance applies ONCE across your total income, not per job. HMRC splits it through tax codes:

• Job 1 (main): typically gets tax code 1257L (the full allowance).
• Job 2 (secondary): typically gets BR (20% on everything), or D0 (40% on everything) if Job 1 already takes you into the higher-rate band.

HMRC reconciles the year using the pay and tax your employers report through payroll, and sends a P800 tax calculation if you paid too much or too little.

National Insurance - the per-job quirk

NI is calculated separately for each employment. Earnings from jobs with the same employer are added together, but earnings paid by different employers are aggregated only in prescribed circumstances (SSCBA 1992 Sch 1 para 1). So each job with a different employer has its own:

• Primary Threshold (PT): £12,570 - NI starts above this.
• Upper Earnings Limit (UEL): £50,270 - the rate steps down above this.
• Main rate (8%): between PT and UEL.
• Upper rate (2%): above UEL.

Because each job has its own PT and UEL, two £40,000 jobs pay £4,389 of NI between them, against £3,611 for a single £80,000 job: neither job reaches the UEL, so none of the earnings get the lower 2% rate. Two £20,000 jobs pay £1,189 against £2,194 for a single £40,000 job, because each job has its own NI-free £12,570.

Worked examples - when two jobs save vs cost NI

Where the break-even falls depends on how the pay is split. With two equal jobs, two jobs pay less NI up to about £67,000 combined and more above it. When two jobs cost more, the calculator’s NI line switches to “Extra NI vs single employment” and shows the extra amount.

Tax codes commonly seen on second jobs

If you see W1 or M1 (week 1 / month 1), tax is worked out non-cumulatively - each pay run is treated as if it were the first of the year. It is common at the start of a second job.

Common errors and how to fix them

1. Both jobs giving the full allowance: each employer applies 1257L. The result is too little tax paid, which HMRC collects after the year ends, usually through your tax code for a later year.

2. Wrong job treated as “main”: if a new second job pays more, you may want the allowance moved to it. You can ask HMRC through your personal tax account or the Income Tax helpline (0300 200 3300).

3. Frequently changing jobs / casual work: tax codes lag reality. Several temporary roles in a year often end with a P800 refund or bill.

4. Statutory pay from one job (maternity, paternity, sick pay) is paid through that employer’s payroll and taxed under its tax code; it does not change the other job’s code by itself.

When to use this calculator

• Considering taking a second job: see net take-home including the NI quirk.
• Just started a second job: check that the two employers’ deductions add up.
• Year-end review: prepare for a P800.
• Negotiating pay at a second job: see the tax rate on your extra income at your total income level.

Self-employed side-hustle vs second PAYE job

Second PAYE job: NI per job, as above. Tax and NI deducted at source.

Self-employed side hustle: declared through Self Assessment. You do not have to pay Class 2 NI: with profits of £7,105 (the Small Profits Threshold) or more, Class 2 is treated as paid to protect your NI record, and below it you can pay voluntarily at £3.65 a week. Class 4 NI is 6% on profits between £12,570 and £50,270 and 2% above. The £1,000 trading allowance covers gross trading income up to that amount.

Class 4 starts at £12,570 of profit and is charged at 6%, against 8% employee NI above £12,570 in a second job, and there is no employer NI - but self-employment means Self Assessment filing and records. See our Class 2 + Class 4 NI deep-dive and Side hustle tax guide.

Student loan with two jobs

If you are employed by more than one employer, student loan repayments are taken only from the jobs where you are paid over your plan’s threshold, not on your combined income (gov.uk). Plan thresholds for 2026/27:

• Plan 1: £26,900
• Plan 2: £29,385
• Plan 4 (Scotland): £33,795
• Plan 5: £25,000
• Postgraduate Loan: £21,000

So a Plan 2 borrower with a £20,000 job and a £15,000 job repays nothing through payroll, although the combined £35,000 is over the threshold. If you also file a Self Assessment return (for example for self-employment income), repayments there are worked out on your combined income for the year; on £35,000 of income that would be £505, less anything already deducted through payroll.

When to merge two jobs into one

If two jobs cost more in NI than a single equivalent, options include:

• Asking for more hours at one role and leaving the other.
• Self-employment for one income stream, but only if the work genuinely is self-employment: employment status rules decide that, not your preference.
• Salary sacrifice into pension at either job, which reduces the pay that job’s NI is charged on.

NI alone rarely drives the decision: career, work-life balance, employer benefits and pension contributions (auto-enrolment is assessed separately for each job, from £10,000 of earnings in that job) usually matter more.

Related calculators and guides

• Salary calculator - test combined income tax
• PAYE Explained - how HMRC splits the allowance between employers
• National Insurance Explained - per-job NI structure
• Emergency Tax What to Do - BR code on second job + fixes
• Side hustle tax guide - alternative to PAYE second job
• Class 2 + Class 4 NI 2026/27 deep-dive - self-employed NI comparison
• Student loan plans explained - thresholds + multiple-job rules
• Pension Auto-Enrolment deep-dive - auto-enrolment applies per employment
• Higher-rate 40% guide - combined income crossing threshold

Sources

Statutory basis: Income Tax Act 2007 (rates + bands), Social Security Contributions and Benefits Act 1992 (NI per employment, Sch 1 para 1), Income Tax (Earnings and Pensions) Act 2003 (employment income), Income Tax (Pay As You Earn) Regulations 2003 (PAYE operation). 2026/27 figures from gov.uk Rates and Thresholds for Employers 2026 to 2027.