Estimate tax on a chargeable gain after costs and the annual exempt amount. Use this when you are selling an asset and want a planning figure before you decide whether to crystallise the gain.
INVESTMENT AND ASSET GAINS
Capital gains tax calculator
Estimated result
£6,960
- Gross gain
- £32,000
- Chargeable gain
- £29,000
- Tax rate used
- 24.0%
A simplified illustration. Your actual rate depends on the asset type, your income and whether reliefs or losses apply.
Estimate the tax on a chargeable gain after costs, reliefs and the annual exempt amount.
Estimate tax on a chargeable gain after costs and the annual exempt amount. Use this when you are selling an asset and want a planning figure before you decide whether to crystallise the gain.
A sale proceeds figure of £75,000 with £40,000 purchase and improvement cost and £3,000 in fees leaves a gross gain of £32,000 before allowances. If the annual exempt amount removes £3,000, the taxable gain is smaller and the tax bill falls accordingly.
- The actual rate depends on your income, the asset type and whether reliefs or losses apply.
- Different assets can qualify for different treatment.
- Reliefs, carry-forward losses and reporting rules can materially change the final figure.
QUICK ANSWER
What is this calculator?
Capital Gains Tax Calculator turns the inputs on this page into a transparent planning estimate for the selected jurisdiction.
How is it calculated?
It uses the displayed inputs, the GB-2026.27.1 ruleset and the assumptions shown beside the result. Different eligibility, timing or household details can change the outcome.
Example
Use the result as an illustrative scenario, then change one input at a time to compare the next decision. It is not an offer or personalised financial advice.
Official source
Capital gains assumptions are checked against GOV.UK’s current CGT guidance.
SOURCES & REVIEW
Checked against official guidance
Last reviewed 4 August 2026 · Rule version GB-2026.27.1
Daily/weekly source monitoring. If a source changes, the affected rule set is reviewed before publication.
Source line: Capital gains assumptions are checked against GOV.UK’s current CGT guidance.
SOURCE LINKS
Every calculation keeps the official references visible so the numbers can be checked quickly.
WHY RESULTS DIFFER
Why two users can see different results
Why the result can differ
Different tax codes, payroll periods, Scottish bands, pension methods or lender assumptions can change the outcome.
One-off bonuses, pay frequency, overpayments, allowances and reliefs can move the result away from a simple annual estimate.
Where a rule depends on eligibility or legal status, this page shows an estimate and links to official guidance.
The explanation stays close to the result so users can compare the assumptions immediately instead of hunting through a separate policy page.
COMMON QUESTIONS
Frequently asked questions
Does the calculator handle every relief?
No. It is a planning estimate and some reliefs need separate checks.
Do income and gains tax bands interact?
Yes. Your income can affect the rate applied to a taxable gain.
Should I use this for a formal return?
No. A formal return may need a tax professional or HMRC filing check.