Two Jobs Tax Calculator

Income tax: one liability, two collectors

Your annual liability depends only on the total, never on how it is split:

Take £48,000 and £10,000. The combined £58,000 less the £12,570 allowance leaves £45,430 taxable: £37,700 at 20% is £7,540.00, and the remaining £7,730 at 40% is £3,092.00. Total due: £10,632.00.

PAYE then collects it through two codes that each see half the picture. The main job on 1257L deducts £7,086.00; the second on BR deducts a flat 20% of £10,000, or £2,000.00. Together that is £9,086.00 against a liability of £10,632.00 — a shortfall of £1,546.00, because BR charged 20% on earnings that belong in the 40% band. A code is an estimate, not an answer.

National Insurance: assessed per employment

HMRC’s National Insurance Manual is explicit that earnings must be aggregated across jobs with the same employer, while jobs with different employers stay separate. Each employment therefore gets its own full threshold:

That single line is why £30,000 plus £8,000 pays £1,394.40 where one job at £38,000 pays £2,034.40: the second job’s earnings fall entirely under its own threshold. It is also why the advantage reverses at the top. Two jobs at £60,000 and £55,000 pay the 8% main rate on two complete bands, handing over £6,321.20 where a single £115,000 job pays £4,310.60.

The relief for that case is the annual maximum in Regulation 21(3), an eight-step calculation defined on weekly figures rather than annual ones: its first step is £967 less £242, multiplied by 53 weeks. Anything paid above the resulting cap is refundable, or avoidable in advance by deferring one employment onto category J with form CA72A. The calculator prints all eight steps whenever your figures exceed the maximum.

Student loan: measured one job at a time

Repayments are charged on earnings above the plan threshold, and gov.uk states you repay only from jobs paid over that threshold, “not your combined income”. The employer guidance is blunter still: if an employee has more than one job, payroll should ignore earnings from the other employer.

A Plan 2 borrower earning £25,000 and £12,000 repays £0.00 across the year, because neither job on its own clears £29,385. The same £37,000 in one job would repay £685.35. Under PAYE that is simply how the rules work; a Self Assessment return, however, assesses total income and closes the gap.

Nadia — full-time admin plus weekend bar shifts

£30,000 on 1257L and £8,000 on BR, England, no student loan.

The BR code on her bar job is not a punishment, it is arithmetically correct: her allowance is fully used at the admin job, so every pound of the second is genuinely due at 20%. The codes collect £5,086.00 against a liability of £5,086.00 — no gap, no bill. The quieter result is the National Insurance one. She pays £640.00 less than someone earning the same £38,000 from one employer, because the bar job’s £8,000 sits entirely below its own £12,570 threshold.

Tom — salaried job plus evening consultancy on PAYE

£48,000 on 1257L and £10,000 on BR, England.

This is the case that inverts most people’s expectations. The dangerous direction is under-taxation, not over-taxation: BR takes 20% of the consultancy work while its top £7,730 actually falls in the 40% band, leaving £1,546.00 to be found later. Switching the second job to D0 collects £11,086.00 instead, which over-collects by £454.00 — a far more comfortable error to make, and refundable. His National Insurance still comes in £336.20 below the single-job equivalent.

Priya — two part-time jobs under the Personal Allowance

£7,000 on 1257L and £5,000 on BR, England.

She owes nothing and is paying £1,000.00. Her combined £12,000 is below the allowance entirely, yet BR takes 20% of the second job every payday and holds it until she reclaims it. Splitting the allowance — 700L on one job and 557L on the other — stops the deduction at source. Worth noting separately: her £7,000 job clears the £6,708 Lower Earnings Limit and so credits a State Pension qualifying year; the £5,000 one does not.

Callum — two jobs and a Plan 2 student loan

£25,000 and £12,000, Plan 2 threshold £29,385, England.

Because each employer ignores the other’s earnings, £37,000 of combined income triggers no student loan repayment at all — neither job reaches the threshold on its own. Against £685.35 for the same money in a single job, that is the largest cash difference between one job and two at this income level, larger than the National Insurance effect. It is entirely legitimate under PAYE. If he is ever pulled into Self Assessment, the return assesses the combined figure and the balance becomes payable.

Dr Osei — two senior contracts, both well paid

£60,000 on 1257L and £55,000 on D0, England.

Two things go wrong at once here, in opposite directions. Above the Upper Earnings Limit the per-employment rule flips from advantage to penalty: he pays the 8% main rate on two full bands, £6,321.20, against an annual maximum of £4,102.70, leaving £2,218.50 recoverable. Meanwhile his combined £115,000 tapers the allowance to £5,070.00, but both codes still hand over the full £12,570 — exactly £7,500.00 of allowance given away, which at 40% is £3,000.00 of tax under-collected. He is simultaneously overpaying National Insurance and underpaying income tax, and neither payslip shows either.

Every rate on this page, and where it comes from

Why is my second job taxed at 40% when I don't earn that much?

A D0 code charges 40% on every pound of that job, and HMRC issues it when its estimate of your main job's pay already fills the basic-rate band. The code is not a judgement about the second job in isolation; it is an attempt to charge the right rate on income that, stacked on top of your main salary, genuinely sits above £50,270. Where it goes wrong is when the estimate has gone stale — a main job whose hours, shift premium or bonus have since fallen leaves you paying 40% on earnings that now belong in the 20% band. Tell HMRC what you actually expect to earn this year through the Check your Income Tax service and ask for the second job to move to BR. Anything over-deducted comes back through a code change during the year, or a P800 after 5 April.

How much can I earn in a second job before paying tax?

For a second employment, usually nothing at all. Your £12,570 Personal Allowance is normally given in full to your main job through a 1257L code, which leaves the second job on BR and taxed from its first pound with no tax-free slice of its own. The £1,000 figure most people have heard of is the trading allowance, and gov.uk confines it to self-employment, casual services and hiring out personal equipment — wages are not covered. There is one real exception. If your main job pays less than the allowance, part of it is sitting idle, and you can ask HMRC to move the unused portion to the second job as a split code. The second job then does get that much tax-free, and the calculator above names the two code numbers to ask for.

Do I pay more National Insurance with two jobs?

Usually less, sometimes considerably more, and the switch happens at a point you can predict. Each employment is assessed separately, so each carries its own £12,570 primary threshold: £30,000 plus £8,000 pays £1,394.40 where a single £38,000 job pays £2,034.40. The saving comes from the smaller job's earnings falling under a threshold that one employer would already have used up. Past the £50,270 Upper Earnings Limit the same rule works against you, because the 8% main rate gets charged on two full bands instead of one. Two jobs at £60,000 and £55,000 hand over £6,321.20 against an annual maximum of £4,102.70. One case removes the effect entirely: if both posts belong to the same legal employer, the earnings must be aggregated and there is no second threshold to gain from. Because income tax comes to the same figure whichever way the money is split, National Insurance is the whole of the difference. The calculator reports which side of the line your figures fall on.

Can I split my Personal Allowance between two jobs?

Yes. Ask HMRC to allocate part of the £12,570 to each employer and you get two codes whose numbers add up to 1257 — 700L and 557L, for instance, giving £7,000 of tax-free pay at one job and £5,570 at the other. What that changes is almost always timing rather than money, because the annual liability is fixed by your combined income and moving allowance between codes only decides which employer deducts it. The exception matters. If your two jobs together pay less than the allowance you owe no income tax whatsoever, yet a BR code still takes 20% of the second job every payday. A split stops the deduction at source instead of leaving you to reclaim it once the tax year has closed. You request it through the Check your Income Tax service or by phone. It takes effect from a future pay period rather than retrospectively, so a request made in February recovers little of that year: ask early.

Will I get a tax bill at the end of the year for my second job?

Possibly, and the reason usually runs opposite to what people expect. BR charges a flat 20% regardless of your other income, so once the two jobs together pass £50,270 the top slice is under-taxed at source when 40% was due. £48,000 plus £10,000 leaves £1,546.00 uncollected across the year. HMRC finds it when both employers' year-end submissions are matched, then issues a P800 or adjusts a future code to claw it back. Nothing has malfunctioned — the codes did exactly what they authorised — but the money is genuinely owed. If this page shows a shortfall for your figures, there are two sensible responses: set that amount aside now, or ask HMRC to move the second job to D0 so the 40% is taken as you go. The shortfall builds evenly across the year, so a code changed in month eight must over-collect on the four months left to catch up. Leaving the second job part-way through the year shrinks the gap without closing it.

Do I pay student loan on both jobs?

Only on a job that individually pays above your plan's threshold. gov.uk states that you repay "from jobs where you're paid over the threshold for your plan type, not your combined income", and the employer guidance instructs payroll to ignore earnings from the other employer completely. On Plan 2, whose threshold is £29,385, jobs paying £25,000 and £12,000 produce no deduction at all, even though the same £37,000 in one job would repay £685.35 over the year. That is correct under PAYE and needs no fixing. It stops being the final answer if you ever file a Self Assessment return, because the return looks at total income — so a repayment that never appeared on a payslip can surface as a balancing payment the following January. A Postgraduate Loan runs alongside an undergraduate plan rather than replacing it, carries its own £21,000 threshold and 6% rate, and is tested job by job in exactly the same way. Select your plan above to see both deductions.

What tax code should my second job be on?

It depends entirely on where the combined figure lands. If your main job already absorbs the whole allowance and the two together stay under £50,270, BR is exactly right — a flat 20%, which is the rate actually due on every pound of the second job. If the pair crosses into the higher-rate band, D0 takes 40% and lands much closer to the true liability, though it over-collects a little unless the whole second job sits in that band. If your main job pays less than the allowance, a split code is the correct answer, because anything else deducts tax you do not owe. Seeing 0T, or an emergency code such as W1, M1 or X, generally means HMRC has not yet matched the two employments and the position will change once it has.

Is it better to work two jobs or ask for more hours in one?

Income tax is indifferent: the liability is computed on combined income either way, so the same total produces the same bill. National Insurance is where the two genuinely diverge. Below the Upper Earnings Limit two employments usually win, because the second collects a fresh £12,570 threshold; above it they lose, sometimes by thousands, because the main rate is charged twice. Student loan tends to favour two jobs as well, since each is measured against the threshold on its own. Weigh against that the things the arithmetic misses — two commutes, holiday entitlement that does not combine, and a State Pension record that needs at least one job clearing £6,708. Workplace pensions cut the same way: automatic enrolment is assessed by each employer separately against a £10,000 earnings trigger, so two jobs paying £8,000 each enrol you nowhere, while £16,000 from one employer brings an employer contribution you would otherwise lose. Put your own numbers in above before treating the National Insurance position as decisive.

How do I tell HMRC about a second job?

In most cases you do not have to start the process. Your new employer runs the starter checklist and reports the employment through its first Full Payment Submission, and HMRC issues a code off the back of that. What you can usefully do is correct and accelerate the result: the Check your Income Tax for the current year service lets you update details of your income from jobs and pensions, and tell HMRC about changes that affect your tax code. That matters because the code applied in the opening weeks is often 0T or an emergency code, which taxes each payday in isolation and rarely reflects where you will end up. Telling HMRC what each job is genuinely expected to pay is the quickest route to correct codes and the smallest reconciliation at the end of the year.

Can I get National Insurance back if I've overpaid across two jobs?

Yes, by two different routes. Contributions above the Regulation 21(3) annual maximum are refundable after the tax year ends, and HMRC's manual states plainly that a refund of Class 1 contributions is available where a contributor pays above the maximum. The better route is not to overpay at all: form CA72A applies to defer contributions on one employment, which moves it to category J and charges 2% rather than 8% between the primary threshold and the Upper Earnings Limit. For the 2026/27 year the application deadline is 14 February 2027. Deferment is worth applying for whenever you expect to pay the full main-rate band twice over. Two things it does not do are worth knowing: it does not reduce what your employers pay in secondary contributions, and it does not damage your contribution record, because the earnings still count towards a qualifying year even at the lower rate. This page shows the annual maximum for your own figures next to what your two employments will actually deduct.

Does my second job affect my Personal Allowance if I earn over £100,000?

It does, and neither payroll department will notice. The allowance is withdrawn at £1 for every £2 of combined income above £100,000 and reaches zero at £125,140 — but each employer only ever sees its own figure, and jobs paying £60,000 and £55,000 both look comfortably below the threshold. Neither code withdraws anything. The true allowance on £115,000 is £5,070.00, so £7,500.00 is still being handed out, which at 40% is exactly £3,000.00 of tax under-collected. This is the largest single reconciliation gap the calculator finds, and it is invisible on both payslips. It also creates the sharpest marginal rate in the UK system: between £100,000 and £125,140 every extra pound is taxed at 40% and removes 50p of allowance, an effective 60%. A pension contribution reduces the adjusted net income the taper is measured against, so paying into a pension is the one reliable way to buy the allowance back.

Do two low-paid jobs still count towards my State Pension?

Only if at least one of them individually reaches the Lower Earnings Limit, £6,708 for 2026/27. Earnings at or above that figure in a single employment credit a qualifying year even though no National Insurance becomes payable until £12,570. Because earnings from different employers are never added together for National Insurance, two jobs paying £6,000 apiece credit nothing at all — a full year of work, no qualifying year — while one £12,000 job would qualify comfortably. 35 qualifying years are needed for the full new State Pension, so a few years in this position is a measurable loss, not a technicality. Where the calculator warns that both jobs fall below the limit, concentrating hours in one of them is the direct fix. Two indirect ones exist: National Insurance credits, awarded automatically for things like claiming Child Benefit for a child under 12, and voluntary Class 3 contributions, which buy a missing year for £956.80. Check your record first: credits you hold may already cover it.