About UK Capital Gains Tax Calculator

What this site is for

Use the CGT calculator to estimate your tax liability on a disposal. Enter sale proceeds, original cost, allowable costs, losses and your taxable income before the gain to see the CGT at 18% or 24%, split across basic and higher-rate bands.

All calculations use published 2026/27 rates including the £3,000 annual exempt amount and the post-October 2024 CGT rates of 18% and 24%.

What we cover

• CGT on shares and securities — 18% basic rate and 24% higher rate, the annual exempt amount, and how other income determines which band applies.
• Residential property disposals — CGT on buy-to-let and second homes, the 60-day reporting deadline for UK property, and how main residence relief works.
• Annual exempt amount — the £3,000 allowance, how it is applied against gains, and how it interacts with losses.
• Capital losses — in-year loss offset, carried-forward losses, bed-and-ISA strategies, and how to report losses to HMRC even when no CGT is due.
• Reporting thresholds and Self Assessment — when a CGT return is required, the 60-day property return, and how to use the HMRC real-time CGT service.
• Planning guides — asset transfer between spouses, part-disposals, gifted assets and business asset disposal relief explained with worked examples.

How the site is maintained

• CGT rates and the annual exempt amount are updated when HMRC confirms the new tax year figures.
• Guides are reviewed at each fiscal event and when HMRC updates its CGT guidance.
• Pages are updated when readers report unclear assumptions or outdated figures.
• We do not publish pages without practical value for a UK CGT audience.

Editorial approach

All content is reviewed against current HMRC and GOV.UK guidance. We prioritise factual accuracy and practical usefulness. Where assumptions are made, they are documented on the methodology page.

This site does not provide financial, tax or legal advice. For decisions about capital gains, consult a qualified tax adviser or accountant.

Editorial ownership and contact

Editorial owner: James Whitfield, a UK personal finance writer with a background in capital gains tax, investment disposals and CGT reporting. James writes about CGT rates, the annual exempt amount and asset disposal planning against HMRC guidance.

For corrections or data-quality feedback: contact page

Last reviewed: May 2026. Tax year: 2026/27.