Two Jobs Tax Calculator UK 2025/26

How Two Jobs Are Taxed in the UK — Complete Guide 2025/26

Working two jobs in the UK is increasingly common, whether that means holding a permanent role alongside a part-time position, freelancing in addition to employment, or taking a second salaried role. The tax rules for multiple employments are straightforward in principle but frequently misunderstood — and errors in tax codes can lead to either overpaying or underpaying tax, both of which create problems down the line.

The Personal Allowance Can Only Be Used Once

Every UK taxpayer has a Personal Allowance — the amount of income you can earn each year before paying income tax. For 2025/26, this is £12,570, and it is frozen at this level until at least 2028. The critical rule is that this allowance is applied to only one source of income, not split automatically across all jobs.

In practice, HMRC allocates your personal allowance to your primary (main) job, which is typically the one you've held longer or which generates more income. That employer receives a standard tax code — usually 1257L — which instructs them to deduct no tax on the first £12,570 of your annual pay, then apply the basic rate (20%) on earnings between £12,570 and £50,270, higher rate (40%) on earnings between £50,270 and £125,140, and the additional rate (45%) above £125,140.

Why the Second Job Is Taxed from £0

Because your personal allowance has already been allocated to job one, your second employer has no allowance to apply. HMRC will issue a BR (Basic Rate) tax code to your second employer, instructing them to deduct 20% on every pound you earn at that job. There is no tax-free element.

This feels harsh — you pay 20% from the very first pound — but it is not double taxation. It simply ensures that your overall tax position across both jobs equals what you would pay if the same combined income came from a single employer. Think of it as each employer collecting tax on their slice, with HMRC reconciling the total at year end.

When BR Becomes D0: Entering the Higher Rate Band

The higher rate band begins at £50,270 of total income (2025/26). If your first job alone pays more than £50,270, then every pound from your second job falls into the higher rate band and should be taxed at 40%. In this case, HMRC issues a D0 code to your second employer, deducting 40% flat on all earnings from that job.

Similarly, if your combined income from all sources exceeds £125,140, the additional rate of 45% applies, represented by the tax code D1. Most workers with two jobs fall into the BR or D0 situation.

National Insurance — Calculated Separately on Each Job

This is one of the most important distinctions in UK two-job taxation: National Insurance (NI) is calculated independently for each employment, unlike income tax where your combined income determines your rate band.

For 2025/26, the employee NI thresholds are:

• Primary Threshold: £12,570/year (£1,047.50/month) — no NI below this per employer
• Upper Earnings Limit: £50,270/year — NI rate is 8% between threshold and UEL
• Above £50,270: NI rate drops to 2% per employer

What this means in practice: if your second job pays less than £12,570, you pay no NI on it at all, even though you pay income tax (via BR code) from the first pound. If your second job pays, say, £18,000, you pay NI only on £18,000 minus £12,570 = £5,430 at 8% = £434 NI annually.

Conversely, it is possible to overpay NI across multiple employments if both jobs pay above the UEL. In this situation you can apply to HMRC for a NI refund after the tax year ends.

How to Tell HMRC About Your Second Job

When you start a second job, you must complete a starter checklist (which replaced the P46) for your new employer. On this form, you declare whether this is your only job, your main job, or a second/additional job. This is crucial — if you tick the wrong box, your employer will apply the wrong tax code and you will over- or underpay tax.

For a second job, you should tick Statement C on the starter checklist, which tells the employer this is not your main job and prompts them to apply a BR, D0, or D1 code as appropriate. Your main employer keeps the 1257L code.

Splitting the Personal Allowance Between Jobs

If your two jobs are relatively similar in size, or if your first job pays less than £12,570, it may be more tax-efficient to ask HMRC to split your personal allowance between the two employers. You can request this by:

• Calling HMRC on 0300 200 3300
• Using the Government Gateway online service (Personal Tax Account)
• Writing to HMRC with your details

HMRC will issue revised tax codes to both employers. For example, if your first job pays £8,000 and second job pays £20,000, HMRC might allocate £8,000 allowance to job one (tax code 800L) and £4,570 to job two (tax code 457L), ensuring neither job deducts unnecessary tax on income that should be tax-free.

Reclaiming Overpaid Tax

Overpayment of tax on a second job is common, especially in the first year of employment when emergency codes may be applied. Here is how to reclaim it:

• P800 tax calculation: After the tax year ends (5 April), HMRC sends a P800 if their records show overpayment. Follow the instructions to claim online or receive a cheque.
• Self Assessment: If you are registered for Self Assessment, report all income on your tax return and any overpaid PAYE is reconciled automatically.
• Contact HMRC directly: Call 0300 200 3300 with your P60 details from all employers. Refunds typically arrive within 6–8 weeks.
• R40 form: For reclaiming tax on savings or other income sources in addition to employment.

Worked Example: Two Jobs Tax Calculation 2025/26