Capital Gains Tax Calculator (UK 2025/26)

Calculate your potential Capital Gains Tax quickly and easily

Estimate your CGT for the 2025/26 tax year using this calculator. It works for shares, crypto, and residential property (excluding your main home). Simply enter your figures below to see an estimate that includes allowances and the current main rates.

📌 Updated for 2025/26

CGT rates were aligned from 30 October 2024. As a result, this calculator uses the current main rates for 2025/26: 18% for basic-rate taxpayers and 24% for higher or additional-rate taxpayers.

🧾 Capital Gains Tax Calculator (UK 2025/26)

📌 Updated for 2025/26: CGT rates were aligned from 30 October 2024. This calculator uses the current main rates for 2025/26: 18% / 24%.

Asset type Your income tax band (estimate) If unsure, choose the band you expect to fall into for the 2025/26 tax year. Sale proceeds (£) The amount you sold the asset for (or market value if gifting). Purchase cost (£) What you originally paid to acquire the asset. Allowable costs (£) Examples: solicitor/agent fees, acquisition & selling costs, and qualifying improvement costs. Routine maintenance, bills, mortgage interest, and running costs are not usually allowable. Annual CGT allowance (£) For 2025/26: £3,000 per person. Update if the allowance changes. Remaining basic-rate band for gains (£) (optional) Optional: If you're near the basic-rate limit, enter remaining headroom to estimate a blended rate. Current CGT main rates (2025/26)

Basic rate: 18% | Higher/Additional rate: 24%
(Carried interest has different rates.)

Results are estimates for educational purposes only. Actual CGT liability may differ based on reliefs, losses, and HMRC rules.

Gain before allowance: —

Allowance applied: —

Taxable gain: —

Estimated CGT payable: —

—

📌 Detailed Breakdown

Step	Amount
Sale proceeds	—
Less purchase cost	—
Less allowable costs	—
Gain before allowance	—
Less annual allowance	—
Taxable gain	—
Estimated CGT	—

Important: Estimate uses the 2025/26 annual allowance (£3,000) and main CGT rates (18%/24%). It does not automatically apply reliefs (e.g., Private Residence Relief), losses carried forward, or special cases (e.g., carried interest). If UK residential property CGT is due, you usually must report and pay within 60 days of completion.

How to Use the Calculator

Start by choosing your asset type and your expected income tax band.
Next, fill in the sale proceeds, what you originally paid, and any allowable costs like fees or improvements.
If it applies, add your annual CGT allowance and any unused portion of your basic-rate income tax band.
Then hit Calculate to see your estimated Capital Gains Tax.
When you’re done, you can click Copy Results to save or share your estimate.

Step-by-Step Example

Sale: £250,000 for shares bought at £180,000
Allowable costs: £6,500
Gain before allowance: Sale minus purchase cost and costs
Apply annual CGT allowance: £3,000
Estimate CGT using your tax band rate: 18% for basic, 24% for higher/additional

Important Notes

This is an estimate for educational purposes only.
Reliefs (Private Residence Relief, losses carried forward, special cases) are not included automatically.
Residential property CGT is usually reported and paid within 60 days of completion.
Always consult HMRC guidance or a qualified accountant for final tax decisions.

Understanding Capital Gains Tax

Understanding Capital Gains Tax
Capital Gains Tax is a tax on the profit you make when you sell or dispose of an asset that has increased in value.
For shares and crypto, standard CGT rates apply. Meanwhile, higher rates may apply to residential property that isn’t your main home.

Tips to Manage CGT Legally
One smart strategy is to use your annual allowance each year, it doesn’t roll over.
You might also consider timing asset sales to stay within a lower tax band.
Additionally, you can offset gains with losses carried forward from previous years, which can significantly reduce your bill.

Stay Updated

Tax rules change regularly, so it’s wise to keep your knowledge current. Bookmark this page or subscribe to updates to ensure your calculations stay accurate.