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FREE TOOL · 2026/27

Capital gains tax calculator

Estimate what you'd owe on an investment disposal this tax year. Nothing is stored, nothing is sent anywhere — the maths runs in your browser.

How it works: your gain is proceeds minus cost and dealing fees. The annual exempt amount (£3,000 for 2026/27) is deducted, and the remainder is added to your taxable income: the part that still falls inside the £37,700 basic rate band is taxed at 18%, and anything above it at 24%. The rate follows the band the gain lands in, not the band your salary sits in — which is why a gain large enough to cross the band is charged at both rates.

Want this calculated automatically across every account you hold — with your real allowances tracked all year? That's what we're building.

What we're building

CGT ESTIMATE · 2026/27FREE
Income after your Personal Allowance and any reliefs. It decides how much of the £37,700 basic rate band is left for your gain. This band is the same across the UK — Scotland's own income tax bands do not apply to capital gains tax.
Gain£6,000
Annual exempt amount−£3,000
Taxable gain£3,000
Room left in the basic rate band£17,700
Taxed at 18%£3,000
Taxed at 24%£0

ESTIMATED CGT

£540

Nothing you type here is stored or sent anywhere — including your income. The maths runs in your browser and the page keeps no record of it.

Estimate only, based on standard rates for shares and funds. Not personal advice.

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