A surprising number of people believe that earning a pound into a higher tax band means all their income is suddenly taxed at the higher rate. It isn't — and understanding why is one of the more reassuring things you can learn about how UK tax works.
Tax is charged in slices, not all at once
UK income tax is banded: different portions of your income are taxed at different rates. A first slice is covered by your tax-free Personal Allowance. The next slice is taxed at the basic rate, the slice above that at a higher rate, and so on. Crucially, moving into a higher band only affects the income within that band — not everything you earn.
The bands change — so check current figures
The exact thresholds, rates and the Personal Allowance amount are set by government and reviewed regularly, and Scotland sets some of its own income tax bands that differ from the rest of the UK. For that reason this guide deliberately avoids quoting specific numbers that would date — check gov.uk for the current bands that apply to you and where you live.
A worked illustration (with placeholder numbers)
Imagine a tax-free allowance, then a basic-rate band, then a higher-rate band. Someone whose income reaches just into the higher-rate band pays: nothing on the allowance slice, the basic rate on the middle slice, and the higher rate only on the small amount above the higher-rate threshold. Their average tax rate across all their income is therefore much lower than the higher-rate headline figure.
Things that interact with the bands
A few wrinkles worth knowing exist — for example, the Personal Allowance can taper away at very high incomes, and pension contributions can affect which band some of your income falls into. These get specific fast, so for anything material, your HMRC personal tax account or a qualified accountant is the right place to check. Our tax code guide covers how your allowance is applied through your payslip.