What Does Minus Income Tax on Your Payslip Mean?

The “minus income tax” line on your payslip is the amount of income tax your employer has withheld from your gross pay and forwarded to the tax authority before paying you the balance. In the UK, that collection happens through Pay As You Earn (PAYE); in the US, it happens through federal withholding based on the Form W-4 you gave your employer. What lands in your bank account is your gross pay minus this figure and any other deductions.

Why the Money Comes Out Before You Get Paid

Both the UK and US run pay-as-you-go tax systems. Instead of letting a full year’s tax bill build up, your employer estimates what you owe each pay period and remits it on your behalf. HMRC requires UK employers to deduct income tax and report it in real time every time wages are paid.¹ US federal law requires every employer making a wage payment to deduct and withhold income tax according to IRS-prescribed tables.²

Employers who fail to withhold or remit face penalties, so payroll teams treat the deduction as non-negotiable.¹ That is why the line appears on every payslip rather than only at year-end.

What Actually Sets the Number: UK Tax Code

If you work in the UK, the single most important thing on your payslip is the tax code, usually printed near your National Insurance number. It tells your employer’s payroll software how much of your income is tax-free and what rates apply to the rest.

The number in the code is your tax-free Personal Allowance divided by ten. The standard Personal Allowance is £12,570, so most employees see 1257L. The “L” means you get the full standard allowance.³ Other letters signal different situations:

BR: all income from this job is taxed at the basic rate with no personal allowance applied, common for second jobs.
T: HMRC needs to review some items with you, so the code includes extra calculations.
K: you have untaxed income (such as company benefits or state pension) that exceeds your personal allowance, so extra tax is collected through wages.
S prefix: Scottish rates apply.

If the code is wrong, every payslip will be wrong. Too low and too much tax is taken; too high and you will owe money later.³

What Actually Sets the Number: US W-4

In the US, the amount withheld each payday depends primarily on how you filled out Form W-4 when you started the job. The IRS suggests updating it each January and after any major life change such as marriage, a new child, or a second job.⁴

The W-4 captures your filing status, whether you hold multiple jobs, and whether you claim credits for dependents. Filing status decides which brackets payroll uses and which standard deduction applies. For 2026 the standard deduction is $16,100 for single filers, $32,200 for married filing jointly, $16,100 for married filing separately, and $24,150 for head of household.⁵

If you hold more than one job, or your spouse also works, Step 2 on the W-4 needs to reflect that. Each employer assumes it is your only job unless you tell them otherwise, and that assumption is where most underwithholding starts.

How the Rate Applies to Your Pay

Both systems are progressive: only income within each band is taxed at that band’s rate. For 2025/26 in England, Wales, and Northern Ireland, the first £12,570 is tax-free, the slice from £12,571 to £50,270 is taxed at 20%, the slice from £50,271 to £125,140 at 40%, and anything above £125,140 at 45%.⁶

Take someone on £60,000. The first £12,570 is tax-free. The next £37,700 is taxed at 20%. Only the remaining £9,730 is taxed at 40%. Total income tax comes to roughly £11,432, not £24,000. That is why the “minus income tax” line on a payslip is often much smaller than a headline rate might suggest.

One catch that surprises higher earners: the Personal Allowance shrinks by £1 for every £2 of income above £100,000 and disappears entirely at £125,140.⁶ The effective marginal rate through that band is 60%, so a promotion or bonus that crosses £100,000 can produce a jarring jump in the deduction line.

Scotland Is Different

Scottish residents pay Scottish income tax rates set by the Scottish Government, and the tax code carries an S prefix (for example, S1257L). For 2026/27, Scotland has six bands: 19% from £12,571 to £16,537, 20% to £29,526, 21% to £43,662, 42% to £75,000, 45% to £125,140, and 48% above that.⁷ Above £43,663, a Scottish payslip shows a noticeably larger deduction than the equivalent English one.

US Federal Brackets

Federal brackets work the same way. For 2026, a single filer pays 10% up to $12,400, 12% to $50,400, 22% to $105,700, 24% to $201,775, 32% to $256,225, 35% to $640,600, and 37% above that; married-filing-jointly thresholds are roughly double at the lower bands.⁵ Federal withholding is only part of the story on a US pay stub: many states also levy income tax at rates ranging from zero to over 13%, and a handful of cities add local income tax on top. Those appear as separate lines.

Why the Total Deduction Can Look Bigger Than Just Income Tax

Income tax is rarely the only thing coming out. A payslip that looks unusually light on take-home pay usually has other lines doing the damage.

In the UK, National Insurance is the second-largest mandatory deduction. For the most common employee category (A), the 2025/26 rates are 8% on weekly earnings between £242.01 and £967 and 2% on anything above.⁸ It is separate from income tax and appears on its own line.

In the US, FICA covers two deductions: Social Security at 6.2% on earnings up to $184,500 in 2026, and Medicare at 1.45% with no cap.⁹ Workers earning above $200,000 also see an Additional Medicare Tax of 0.9% kick in.¹⁰

Then there are the deductions you signed up for: workplace pension contributions in the UK, 401(k) or 403(b) contributions in the US, health insurance premiums, and student loan repayments. Some are “pre-tax” and reduce the income your tax is calculated on; others are “post-tax.” If your payslip looks like a large chunk went missing this month, a recent benefits enrollment is a more likely explanation than a tax code error.

If the Income Tax Line Looks Wrong

In the UK, sign into your HMRC Personal Tax Account. From there you can check the current tax code and Personal Allowance, see if the code has recently changed, and update your income details.¹¹ If HMRC agrees the code needs changing, it issues a coding notice to your employer and payroll deductions adjust from the next pay period.¹²

If too much tax was collected across a full tax year, HMRC will usually send a P800 tax calculation letter. You can claim a refund online by bank transfer within about five working days, or wait for a cheque within 14 days of the letter’s date.¹³ If the P800 shows an underpayment, it will explain whether HMRC will collect it through next year’s code or whether you need to pay directly.

In the US, start with the IRS Tax Withholding Estimator. You’ll need your recent pay stubs showing year-to-date earnings and withholding. The tool works through your income, deductions, and credits, then generates a pre-filled Form W-4 to submit to your employer.¹⁴ There is no government coding notice in the US system; you control withholding by handing your payroll department a new W-4 whenever you like.

Getting it close matters because the IRS charges an underpayment penalty if too little is paid across the year. Generally, you need to have paid at least 90% of the current year’s liability or 100% of last year’s (110% if last year’s income was over $150,000) through withholding and estimated payments.¹⁵ Even a year that ends in a refund can carry a penalty if the payments were unevenly spread. The 2026 return and any remaining balance are due April 15, 2027; an extension covers paperwork only, not payment.¹⁶

1
GOV.UK. HMRC Internal Manual – Compliance Handbook CH152200
2
Office of the Law Revision Counsel. 26 USC 3402 – Income Tax Collected at Source
3
GOV.UK. Tax Codes – What Your Tax Code Means
4
Internal Revenue Service. About Form W-4, Employee’s Withholding Certificate
5
Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026
6
GOV.UK. Income Tax Rates and Personal Allowances
7
Scottish Government. Scottish Income Tax 2026 to 2027 – Technical Factsheet
8
GOV.UK. National Insurance Rates and Categories – Contribution Rates
9
Social Security Administration. Contribution and Benefit Base
10
Internal Revenue Service. Questions and Answers for the Additional Medicare Tax
11
GOV.UK. Check Your Income Tax for the Current Year
12
Legislation.gov.uk. The Income Tax (Pay As You Earn) Regulations 2003
13
GOV.UK. If Your Tax Calculation Letter (P800) Says You’re Due a Refund
14
Internal Revenue Service. Tax Withholding Estimator
15
Internal Revenue Service. Quarterly Interest Rates
16
Internal Revenue Service. Individual Tax Filing