Getting started · 6 min read · Updated July 2026 · Written by the Filed Tax team

How much tax will I actually pay?

One of the most common first-timer worries is simply not knowing what the bill will be. Here's how it's worked out — the same building blocks every time — so you can see roughly where you'll land.

You're taxed on your profit — what you earned after allowable costs — not your total takings. And the first slice of that profit is tax-free.

Income Tax: the bands

For the 2025/26 and 2026/27 tax years (these figures are frozen until April 2028):

Only the income within each band is taxed at that band's rate — so earning a pound into the higher rate doesn't push all your income up to 40%. Note the personal allowance shrinks once your income passes £100,000, and disappears entirely at £125,140.

National Insurance: the bit people forget

On top of Income Tax, self-employed people pay Class 4 National Insurance on their profits:

Class 2 National Insurance used to be a separate flat weekly charge, but since April 2024 you no longer have to pay it if your profits are above the small profits threshold — you still get the benefit towards your State Pension for free.

A rough worked example. Say your profit for the year is £30,000. The first £12,570 is tax-free. The remaining £17,430 is taxed at 20% (about £3,486 Income Tax), plus 6% Class 4 NIC on the same slice (about £1,046). So very roughly £4,500 in total — though your own figure depends on other income, reliefs and allowances.

Why the first year can feel like a shock

If your bill is over £1,000, HMRC also asks for payments on account — an advance on next year's tax. That can make the first January bill feel almost double, so it's well worth knowing about before it lands.

The simplest way to know for sure

These bands give you a ballpark, but your real number depends on your full picture — expenses, other income, allowances. Working that out accurately, and making sure you don't overpay, is exactly what we do.

Know your number, with no nasty surprises

We work out what you owe, claim everything you should, and file it — from £25 a month.

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Related guides

This guide is general information, not personal tax advice. Rates, bands and thresholds can change at each Budget — always confirm the current figures on GOV.UK or ask us to check. Figures reflect the 2025/26–2026/27 tax years.

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