Taken on a second job and seen a chunk of it disappear in tax? You're not being penalised for working twice. You're just seeing how your one tax-free allowance, and the codes HMRC uses to apply it, play out across two pay packets.
This guide explains how second job tax works for the 2025/26 tax year. We cover the BR, D0 and D1 tax codes, how your personal allowance is shared, what you pay on employed versus self-employed second income, and how to check you're not overpaying.
It's written for people in England, Wales and Northern Ireland. Scotland sets its own Income Tax rates and bands, so the rates below don't apply there.
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Is it legal to have two jobs in the UK?
Yes. There's no law stopping you from holding more than one job. The thing to check first is your employment contract.
Some contracts include clauses that limit secondary work, usually to protect against a conflict of interest. A contract might stop you from:
- working for a competitor, client or supplier
- taking on work that could harm your employer's reputation
- freelancing in the same field as your main role
If your contract says nothing about second jobs, you're generally free to proceed. If you're unsure, ask HR before you commit.
There's also a working-hours point. Your employer can't normally require you to work more than an average of 48 hours a week unless you sign an opt-out. That limit applies across all your jobs combined, so factor in both roles. You can read the rules on GOV.UK's maximum weekly working hours guidance.
Importantly, a second job doesn't reduce your employment rights. You're entitled to at least the National Minimum or Living Wage, holiday pay and (where eligible) statutory sick pay in each role.
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Do you need to tell HMRC about a second job?
It depends on the type of work.
Employed in both jobs. You don't need to contact HMRC yourself. When you give your second employer a completed starter checklist, they report it to HMRC and set up your payroll. It's still worth checking your tax code online a few weeks after your first payday.
Employed plus self-employed. If your second income is from self-employment (freelancing, a small business or most gig work), you'll usually need to register for Self Assessment. Nobody runs payroll for self-employed work, so you declare it and pay the tax yourself on an annual return.
Self-employed in both. If you're already registered for Self Assessment, your existing registration covers all your self-employed income. You report it together on one return.
There's one threshold to know. If your gross self-employed income for the year is £1,000 or less, the trading allowance means you usually don't need to register or pay tax on it. Go over £1,000 and you generally must register and declare the lot.
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What tax code do you get for a second job?
Book a free Tax Health Check →
This is where most of the confusion comes from, so let's be precise.
Everyone gets one personal allowance, the amount you can earn before paying Income Tax. For 2025/26 it's £12,570. HMRC normally attaches the whole allowance to your main job, which is why that job usually carries the 1257L code.
Your second job then gets a code with no allowance in it, because the allowance is already in use. According to HMRC, the common codes are:
| Tax code | What it means | When it applies |
|---|---|---|
| BR | All income from this job is taxed at the basic rate (20%) | Most second jobs, where combined income stays in the basic-rate band |
| D0 | All income from this job is taxed at the higher rate (40%) | When the second job sits inside the higher-rate band |
| D1 | All income from this job is taxed at the additional rate (45%) | When the second job sits inside the additional-rate band |
These definitions come straight from HMRC's tax code guidance. Most people with a second job will see BR on that payslip and pay 20% on every pound of it.
For reference, the 2025/26 Income Tax bands for England, Wales and Northern Ireland are:
| Band | Taxable income | Rate |
|---|---|---|
| Personal allowance | Up to £12,570 | 0% |
| Basic rate | £12,571 to £50,270 | 20% |
| Higher rate | £50,271 to £125,140 | 40% |
| Additional rate | Over £125,140 | 45% |
Source: GOV.UK Income Tax rates and allowances. The personal allowance also tapers away by £1 for every £2 of income over £100,000, reaching nil at £125,140.
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Can you split your personal allowance between two jobs?
Yes, in the right circumstances. If your main job pays less than the £12,570 allowance, some of it goes unused, and a BR code on your second job would tax income that shouldn't be taxed at all.
In that case you can ask HMRC to split your allowance across both jobs so each gets a share. You can do this through your Personal Tax Account or by phoning HMRC.
A word of caution. Only split if your income is stable and predictable. If you're on a zero-hours or irregular contract and you earn more than expected, you can tip over the allowance and end up owing tax later. When earnings are unpredictable, leaving the allowance on one job is often the safer choice.
Illustrative example: splitting a low combined income Priya earns £8,000 from her main job and £3,000 from a weekend role. Her combined income of £11,000 is below the £12,570 personal allowance, so she shouldn't pay any Income Tax. Left on a default BR code, her second job would be taxed at 20%, costing her £600 she doesn't owe. By asking HMRC to split her allowance, both jobs fall within it and she pays nothing.
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How much tax do you pay on a second job?
It comes down to your total income across both jobs, not the jobs in isolation. Your allowance is used once, then everything above it is taxed at the band it falls into. Here are three worked examples, all using 2025/26 figures and Income Tax only (National Insurance is covered separately below).
Illustrative example 1: main job above the allowance Sam earns £35,000 as an IT technician and £7,500 from part-time IT security work. - Main job (1257L): £35,000 − £12,570 = £22,430 taxed at 20% = £4,486 - Second job (BR): £7,500 × 20% = £1,500 - Total Income Tax: £5,986 Sam's allowance is fully used by his main job, so the whole second job is taxed at 20%.
Illustrative example 2: combined income below the allowance Lacy earns £8,500 as a trainee beautician and £2,500 as a cleaner. Her combined £11,000 is below the £12,570 allowance, so she owes no Income Tax on either job. Left on a default BR code, her second job would be taxed 20% = £500 she doesn't owe. The fix is to ask HMRC to split her allowance across both jobs.
Illustrative example 3: second job crosses into the higher rate Frankie earns £50,000 from her main job and £8,000 from a second role. Combined income is £58,000, which crosses the £50,270 higher-rate threshold. - Main job (1257L): £50,000 − £12,570 = £37,430 taxed at 20% = £7,486 - Second job: the first £270 falls in the basic-rate band (£270 × 20% = £54); the remaining £7,730 is taxed at 40% (£7,730 × 40% = £3,092), so £3,146 - Total Income Tax: £10,632 Because part of her second job spills into the higher rate, a flat BR code would under-collect. Frankie should ask HMRC to update her codes so the right amount is taken across the year, rather than facing a bill at year end.
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Do you pay National Insurance on a second job?
National Insurance (NI) works differently from Income Tax. It's worked out separately for each employed job, on that job's earnings, not on your combined total.
For 2025/26, employee (Class 1) NI is charged at 8% on earnings between the Primary Threshold and the Upper Earnings Limit, and 2% above it. The Primary Threshold is £242 a week (£1,048 a month, £12,570 a year) and the Upper Earnings Limit is £967 a week (£4,189 a month, £50,270 a year).
Because each job is assessed on its own, a second job that pays below £242 a week attracts no employee NI at all, even if your other job pays well over the threshold. That's a genuine quirk that can leave you paying slightly less NI than someone earning the same total from a single job.
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What if your second income is from self-employment?
If your second income is freelancing, a small business or gig work (think delivery driving or content creation), it's self-employed income and the process is different.
Once you go over the £1,000 trading allowance, you register for Self Assessment and report your self-employed profit (income minus allowable expenses) on an annual return. HMRC adds that profit to your employed earnings, works out the total tax due, then credits the tax already taken through your job's payroll. You pay the difference.
If you're juggling employment and a side business, our self-assessment service takes the return off your plate, and the self-employed tax calculator gives you a quick estimate of what to set aside.
Illustrative example: employed plus self-employed Maya earns £25,000 from employment and makes £10,000 profit from freelancing. - Total income: £35,000 - Personal allowance (£12,570) is set against her employed pay first - Her £10,000 freelance profit sits within the basic-rate band, so Income Tax on it is £10,000 × 20% = £2,000 She pays that £2,000 through Self Assessment, on top of the tax already deducted from her job.
On top of Income Tax, self-employed profits attract Class 4 NI. For 2025/26 that's 6% on profits between £12,570 and £50,270, and 2% above £50,270. Class 4 is charged on your self-employed profits in their own right, not on your combined income. So Maya's £10,000 profit, which is below the £12,570 lower limit on its own, attracts no Class 4 NI. It pays to model this before the deadline if your profits sit near the limit.
A common myth is that you still pay a flat weekly Class 2 charge. You don't. Since 6 April 2024, Class 2 is no longer collected as a flat charge for most people. If your profits are at or above the Small Profits Threshold (£6,845 for 2025/26) you're treated as having paid it, so your NI record is protected without a payment. If your profits are below that, you can pay Class 2 voluntarily at £3.50 a week to keep your record complete. Both figures come from GOV.UK's self-employed NI guidance.
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How do you check you're paying the right tax on a second job?
A few habits stop problems before they start.
Complete the starter checklist accurately. When you start a second job, your employer asks you to fill in HMRC's starter checklist. If you already have another job, pick the statement that says so (Statement C). Don't declare it as your only job, or you'll wrongly get a second full allowance and underpay tax now, only to be billed later.
Check your first payslip. Look at the tax code (usually BR for a second job, or D0/D1 if you're a higher earner), the tax deducted, and that your NI number is right. If something looks off, speak to payroll straight away.
Watch for 1257L on both jobs. If your second job shows 1257L, you're getting two full allowances. HMRC will catch it and reclaim the underpaid tax, so fix it early.
Use your Personal Tax Account. Log in to check your Income Tax for the current year, confirm both jobs are listed, and check the codes are right. A quick look at the start of each tax year is sensible.
To sanity-check the numbers yourself, try our income tax calculator and take-home pay calculator.
If you have a student loan, repayments are assessed on each PAYE source separately, against the threshold for your repayment plan, so a smaller second job often won't trigger any repayment. You can confirm your current plan and threshold on GOV.UK's student loan repayment guidance.
Want help getting your second job tax right?
Two income sources, two tax codes, and an annual return to file if one of them is self-employed. It's easy to overpay or get caught out. Zmartly checks your codes, handles your Self Assessment, and makes sure you're claiming everything you should. Book a free 20-minute call with a Zmartly accountant and we'll sort it.
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How do you claim back tax you've overpaid on a second job?
Tax code errors happen, and they're fixable. You may have overpaid if you had a BR code while your total income was below the allowance, if both jobs gave you 1257L and one was later corrected, or if your codes weren't updated after a change.
Start by asking your employer to check the code with HMRC and correct it for future pay. After the tax year ends, HMRC reconciles everyone's records and issues a P800 calculation where there's an over or underpayment. If you're owed money, you'll usually be able to claim it online, with the refund paid to your bank.
You can reclaim overpaid tax for up to four earlier tax years, so it's worth acting promptly if you spot an old error.
One safety note. HMRC will never text or email you offering a refund in return for your bank or card details. Those are scams. Only ever check your tax position through your official Personal Tax Account.
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FAQs about second job tax
Do you get taxed more just for having two jobs?
No. You're not penalised for having two jobs. Your overall tax simply reflects your total income for the year. Tax is worked out on everything you earn, not per job, so the more you earn the more tax you pay, whether it comes from one job or two.
What is the BR tax code for a second job?
BR stands for basic rate. It means all the income from that job is taxed at 20%, with no tax-free allowance applied, because your allowance is already used by your main job. BR is the most common second job code. If your combined income reaches the higher or additional rate, you may get a D0 (40%) or D1 (45%) code instead.
Do you need a P45 for a second job?
No. You only have a P45 when you leave a job. Since you're keeping your first job, you won't have one to give your second employer. Instead you complete HMRC's starter checklist and select the statement confirming you have another job.
Do you pay National Insurance on a second job?
Only if that job pays you above the Primary Threshold, which is £242 a week for 2025/26. National Insurance is assessed separately for each employed job, not on your combined earnings, so a second job paying below that threshold attracts no employee NI even if your main job is well above it.
Can you split your £12,570 personal allowance between two jobs?
Yes, if your total income from both jobs is below £12,570 you can ask HMRC to split your allowance so neither job overtaxes you. Do this through your Personal Tax Account or by phone. It's best avoided if your income is unpredictable, as earning more than expected could leave you owing tax.
Do I need to file a tax return if I have two employed jobs?
Usually not, as long as both are PAYE jobs and your tax codes are correct, because the tax is handled through payroll. You will need to register for Self Assessment if your second income is self-employed and exceeds the £1,000 trading allowance, or if HMRC asks you to file.
What tax do I pay on gig work like delivery driving?
Most gig work is self-employed income. You pay Income Tax at your usual rate on your profit (income minus allowable expenses) and Class 4 National Insurance on those profits. If your gross self-employed income tops £1,000 in a tax year, you must register for Self Assessment and declare it.
