Understanding Your Payslip

Most employed people glance at the figure that lands in their account each month and leave it at that. The rest of the payslip — rows of deductions and codes — gets ignored. Your payslip is a surprisingly useful document if you know how to read it. It tells you whether your tax code is right, whether your pension contributions are being made correctly, and whether anything has gone wrong that needs catching.

Understanding what comes out, and why, helps you check that your tax code is correct, track your pension contributions, and spot errors before they compound over months or years.

Gross pay vs net pay

Gross pay is what you earn before anything is deducted. Net pay is what lands in your account. The difference between the two is made up of income tax, National Insurance contributions, and any pension contributions your employer deducts at source. Some payslips also show student loan repayments or salary sacrifice deductions.

That gap between gross and net can feel significant, particularly early in a career. Knowing what each deduction is for makes the system feel less like money disappearing and more like money doing specific things.

Your tax code

Your tax code tells your employer how much of your pay to tax. The most common code in England, Wales, and Northern Ireland is 1257L, which means you can earn £12,570 in the tax year before paying income tax. If your code is different, and many are, it's worth knowing why.

If your code has a letter K at the start, it means deductions exceed your personal allowance and tax is being collected on additional income. BR means all your pay from that source is being taxed at the basic rate, which is common for a second job. If anything looks unfamiliar, HMRC's online personal tax account lets you check and update your code.

National Insurance

National Insurance contributions (NICs) are deducted from earnings above the Primary Threshold of £12,570 per year. The standard employee rate is 8% on earnings between that threshold and the Upper Earnings Limit (£50,270), and 2% on everything above it. NICs fund state benefits including the NHS, and they build your entitlement to the State Pension. One detail worth knowing: you start building qualifying years for State Pension at a lower threshold — the Lower Earnings Limit, currently £6,708 per year (£129 per week). If you earn between the LEL and the Primary Threshold you pay no NI, but the year still counts towards your State Pension record. Each qualifying year builds your entitlement towards the full new State Pension, which requires 35 qualifying years in total.

Pension contributions

If you're enrolled in a workplace pension, your contribution will appear as a deduction on your payslip. Under auto-enrolment rules, the minimum total contribution is 8% of qualifying earnings, split between you and your employer. Your share is typically 5%, your employer's is 3%, though many employers contribute more.

It's worth checking whether your pension is set up as a salary sacrifice arrangement. Under salary sacrifice, you formally agree to a lower gross salary, and your employer pays the difference directly into your pension. This reduces both your income tax and your NI on that portion — a meaningful saving — but it also lowers the salary figure used in mortgage applications, maternity pay calculations, and salary-based life cover. For most people the trade-off is worth it; it's worth knowing the trade-off exists.

Key payslip lines to check each month

Benefits in kind

If your employer provides benefits such as a company car, private medical insurance, or a gym membership, these may appear on your payslip as a notional value. They don't come out of your pay directly, but they affect your taxable income and therefore your tax code. The annual P11D form your employer submits to HMRC captures these. If you receive benefits in kind and your tax code hasn't changed to reflect them, it's worth querying.

When to look more closely

Most months, a quick check is enough. Review more carefully after a pay rise, a change of role, the start of a new tax year, or any change to your benefits. Errors happen often, and they are much easier to resolve in the month they occur than six months later when HMRC has already reconciled at year-end.