Capital Gains Tax Calculator

Estimate Capital Gains Tax on shares, investments, a second property or another chargeable asset. The result uses the 2026/27 annual exempt amount and income-based CGT bands.

What Capital Gains Tax applies to

Capital Gains Tax can apply when an asset is sold or otherwise disposed of for more than its allowable cost. Common examples include investments held outside an ISA, second homes, buy-to-let property and some valuable personal possessions.

Working out the gain

The gain starts with sale proceeds minus the purchase cost and qualifying buying, selling and improvement costs. The annual exempt amount is then deducted from total net gains before the tax rates are applied.

How taxable income affects the rate

For gains from 6 April 2026, the part that fits within the unused basic-rate Income Tax band is charged at 18%. Any remaining taxable gain is charged at 24%. This is why the calculator asks for taxable income rather than gross salary.

Worked examples

Selling investments outside an ISA

If sale proceeds are £75,000 and total purchase and allowable costs are £45,000, the gain before the annual exempt amount is £30,000. The rate split then depends on taxable income.

Selling a main home

A main home can qualify for Private Residence Relief, so a standard CGT estimate may not be appropriate. Check the detailed eligibility rules before relying on a figure.

How we calculate this

Sale proceeds are reduced by purchase cost, qualifying improvement costs and qualifying transaction costs.

The 2026/27 Annual Exempt Amount of £3,000 is deducted from the gain where available.

The taxable gain is charged at 18% to the extent that it fits within the remaining £37,700 basic-rate band, with the balance charged at 24%.

Official sources

FAQs

What is the Capital Gains Tax annual exempt amount?

The individual Annual Exempt Amount is £3,000. It applies to overall net gains for the tax year, not separately to each asset.

Can I deduct improvement costs?

Qualifying capital improvements that add lasting value may be deductible. Routine maintenance and normal repair costs are generally treated differently.

Does this include capital losses?

No. Current-year and brought-forward allowable losses can reduce taxable gains, so the actual liability may be lower than this simplified estimate.

Is selling my home taxable?

A main residence is often covered by Private Residence Relief, but the relief depends on ownership and occupation history. Second homes and buy-to-let property can be taxable.

Money

Save vs Invest

Compare saving and investing for risk, access, inflation and long-term growth.

Read comparison

Read the full comparison

Saving protects capital and works best for short-term goals. Investing offers higher long-term growth potential but comes with volatility and loss risk. Most people need both: cash for emergencies and near-term plans, investments for longer-term wealth building.

Related tools

Calculator

Compound Interest Calculator

Estimate how compound interest can grow over time.

Use calculator