Gross pay is what your employer promises you. Net income is what actually lands in your bank account, and the gap between the two surprises most people.
A basic-rate employee earning £35,000 in 2025/26 will see roughly £7,700 disappear before their salary hits their current account. That gap, between what you earn and what you keep, is precisely what the term net income describes, and understanding it is the difference between budgeting on paper and budgeting in reality.
Every conversation about pay starts with gross income, the headline figure before the government takes its share. Net income is what survives that process. The two numbers live at opposite ends of the same calculation, and confusing them is one of the most common financial mistakes people make when accepting a job offer, applying for a mortgage or estimating their tax bill.
For employees, the journey from gross to net runs through PAYE (Pay As You Earn). Your employer deducts Income Tax and National Insurance at source, then pays the remainder into your account. For the self-employed and sole traders, the route is less automatic: you pay tax and Class 4 National Insurance through Self Assessment, which means your bank account temporarily holds money that does not actually belong to you.
The calculation follows a clear order of operations. Start with gross earnings, subtract the Personal Allowance, apply the relevant Income Tax bands to what remains, then subtract National Insurance. Any other deductions, pension contributions, student loan repayments, charity giving through payroll, come off on top.
Suppose you are a freelance graphic designer with £40,000 of profit in 2025/26, after deducting allowable business expenses from revenue.
| Step | Amount |
|---|---|
| Gross profit (after expenses) | £40,000 |
| Less: Personal Allowance | (£12,570) |
| Taxable income | £27,430 |
| Income Tax at 20% | (£5,486) |
| Class 4 NI at 6% (£12,570 to £50,270) | (£1,646) |
| Class 2 NI (flat rate, if applicable) | (£179) |
| Net income | £32,689 |
That means roughly 18p in every pound earned is going to HMRC before you see it, even at a relatively modest profit level. Use the salary and income tax calculator to run your own figures in seconds.
People often treat net income and take-home pay as identical, and in casual use that is mostly fine. Technically, though, they can diverge. Net income usually refers to your post-tax earnings as a figure on paper, the amount HMRC or a lender sees when assessing your finances. Take-home pay is the physical cash deposited in your account, which may be lower still if your employer is also deducting pension contributions, season-ticket loans or a salary-sacrifice arrangement for a company car or cycle scheme.
For mortgage affordability assessments, lenders will typically ask for net income rather than gross salary, precisely because it reflects your real spending power. Overstating this figure, even accidentally, can cause problems at offer stage.
The Personal Allowance is the most powerful lever on your net income at standard earnings levels. In 2025/26 it sits at £12,570, meaning the first £12,570 you earn attracts zero Income Tax. A basic-rate taxpayer earning exactly £20,000 therefore only pays tax on £7,430, not on the full £20,000.
There are two important caveats. First, the allowance begins to taper once your adjusted net income exceeds £100,000: for every £2 you earn above that threshold, you lose £1 of allowance, creating a brutal effective 60% marginal tax rate for earnings between £100,000 and £125,140. Second, the allowance can be increased by Marriage Allowance transfers or reduced by a tax code adjustment if you owe money from previous years.
Most people account for Income Tax and NI but overlook the following:
From April 2026, sole traders with income above £50,000 will be required to report trading income quarterly under Making Tax Digital for Income Tax (MTD for ITSA). From April 2027, the threshold drops to £30,000. This does not change how net income is calculated, but it does change how often you need to have a clear picture of it. Quarterly digital submissions will make the gap between gross profit and net income visible four times a year rather than once, giving you far less room to be surprised at the January 31 payment deadline.
Net income is the number your bank balance actually reflects; every financial decision you make should be anchored to it, not to your salary headline.
TapTax connects to your bank, categorises expenses automatically, and submits quarterly updates to HMRC. Free plan, no card required.
