Many people take on a second job to make some extra money, or as a stepping stone to starting their own business. But they might be unaware of their rights around taking a second job, and how they’ll pay tax and National Insurance on it.
What’s in this guide
Can my employer stop me from having a second job?
One of the first questions you need to ask yourself is if your existing contract of employment lets you take on a second job.
You should have been given a copy of your contract when you started working for your employer. If you don’t have one, your employer or HR department should be able to provide you with one.
Your employer might rule out you taking on extra jobs in situations where:
- there might be a conflict of interest, for example working for a rival company
- your second job might bring your employer into disrepute.
If you’re not sure, check your contract. If there’s nothing about second jobs stated in it, your employer can’t prevent you from taking another job.
What are my rights when working a second job?
Rights and contracts
Depending on your employment status, you’re entitled to rights at work, regardless of whether it’s your first or second job.
Find out more in our guide Different kinds of employment status
Whatever your employment status is – if you’re employed by someone else, you should have an employment contract.
This should set out, among other things:
- job title
- responsibilities
- pay
- hours of work
- the benefits you’re entitled to.
Find out more in our guide Employment contracts and your employee rights explained
National Minimum Wage
Almost all workers in the UK are entitled to be paid at least the National Minimum Wage – or the National Living Wage if you’re 23 or over. From 1 April 2024, it will also apply to workers over the age of 21.
Find out more in our guide National Minimum Wage
Working hours
By law, your employer can’t ask you to work more than an average of 48 hours a week in a single job.
However, if you’re over 18 you can choose to work more hours than this. And you might need to if you want to take on a second job.
Find out more about maximum weekly working hours at GOV.UKOpens in a new window
Income Tax on second jobs
If you’re working, you’re entitled to earn a certain amount of money without paying Income Tax. This is called the Personal Allowance and is £12,570 for the 2023/24 tax year.
You only get one Personal Allowance – so it’s usually best to have it applied to the job paying you the most.
If you work two jobs and neither income is above £12,570, you can split your Personal Allowance.
Find out more in our guide about How Income Tax and the Personal Allowance works
Example 1: if you have two jobs
Jane works two jobs. Her main job pays £14,000 a year, and the second £6,000.
Her whole Personal Allowance is applied to her main job. If she lives in England, Wales or Northern Ireland, she pays Income Tax at the basic rate of 20% on the £1,430 of her pay that’s above the allowance for her main job - – and on all her income from her second job
Income Tax is different in Scotland. Find out more in our guide Scottish Income Tax and National Insurance
Example 2: two jobs below the Personal Allowance
Richard has two jobs. His main job pays £10,000 a year and his second £9,000.
Both of these are below the Personal Allowance, so he can split his allowance between the two jobs.
He can contact HMRC and get them to transfer £2,570 of unused allowance from his main job to his second job. Or he can wait until the end of the tax year, and ask HMRC for a refund.
You should only ask for your Personal Allowance to be split if your income from each job is predictable and stable. If it’s not, and one job ends up paying you more than expected, you’ll have underpaid tax.
If you have questions about Income Tax, contact details for HMRC are at GOV.UKOpens in a new window
Example 3: if your combined earnings are over £50,000
Rebecca’s main job pays her £45,000 a year. But she also has a part-time job paying £12,000 a year. This means she has a total income of £57,000, with all her Personal Allowance being applied to her main job.
Unless Rebecca tells HMRC this, her second job will be taxed entirely at the basic rate, when some of it should be taxed at the higher rate.
If she doesn’t tell HMRC this, she’ll have to pay extra tax at the end of the tax year.
Tax codes for second jobs
It’s important to check your tax codes. This will help make sure you’re paying the right amount of tax and don’t get unexpected tax bills, penalty charges and interest.
Your main job, assuming it pays you more than the Personal Allowance, should be 1257L for the 2023/24 tax year.
Your second job should have a BR, D0 or D1 tax code, depending on whether or not it’s taxed at the basic, higher or additional rate.
You can find your tax code on your payslips.
You can tell HMRC about starting a second job using the new starter checklist from your new employer.
If you weren’t given a new starter checklist, you can download one from GOV.UK Opens in a new window
National Insurance on a second job
If you earn above £242 a week in the 2023/24 tax year, you’ll have to pay Class 1 National Insurance contributions.
If you earn more than this in both of your jobs, you’ll pay National Insurance contributions on both jobs.
How will having a second job affect my benefits?
Taking a second job can affect your tax credits or other benefits. So you need to work out how much extra you’ll be earning.
If you’re claiming Universal Credit, and aren’t getting the work allowance, your payment will go down 63p for every £1 earned.
Find out more in our guide Universal Credit explained
If you’re still claiming Working Tax Credit, you’ll need to tell the Tax Credit Office if your income changes by more than £2,500. But this might count as a change in circumstances and could mean you have to make a new claim for Universal Credit.
Find out more about how income changes affect Working Tax Credit in our guide
Working Tax Credits
Second job and pensions
Taking a second job might give you the opportunity to pay into another workplace pension scheme. But remember to keep track of any small pensions you’ve paid into.
If you pay a small amount into a pension in your second job, it might be worth combining it with a larger pension when you leave.
If you’re already receiving your State Pension, or you have a private or occupational pension, and you work as well, it can have tax implications.
Again, it’s important to make sure you’re paying the correct amount of tax and have the right tax code.
Find out more about your workplace pension, and the benefits of paying into it, in our guide Automatic enrolment – an introduction
Self-employed as a second job
If you’re working your second job as self-employed, you’ll need to:
- register as self-employed with HMRC
- file a Self Assessment tax return by 31 January each year
- pay your own tax and National Insurance contributions.
Find out more in our guide Tax and National Insurance when you’re self-employed
It’s important to check your National Insurance record regularly. Find out how at GOV.UKOpens in a new window
As you’re self-employed, you won’t get a payslip. So you’ll have to be careful about your tax code on your other job.
Usually, the job paying you the most should be classed as your main job.
However, if your second job is self-employed you might not know exactly how much you’re earning. This makes it potentially difficult to make sure your full Personal Allowance is being taken.
If both jobs are paying you below the Personal Allowance, you’re still entitled to split your allowance between them.
If one of your jobs is self-employed, you’ll pay tax and National Insurance contributions a year in arrears.
For example, for the money you earned in the 2022/23 tax year, you’ll need to pay the outstanding tax and National Insurance contributions by 31 January 2024.
This means it’s important you think about how you’ll pay what could be a substantial bill. The good news is, you should have an idea about how much tax you’ll owe at the end of the previous tax year. This gives you nine months to prepare.