Capital Gains Tax Advice & Calculation Services

What is 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. It applies to assets such as property (that is not your main home), shares, and certain other investments. The taxable capital gain is typically the difference between what you paid for the asset (plus allowable costs) and what you sold it for. Not all gains are taxed: you have an annual exempt amount (CGT allowance) each year, and some assets and reliefs can reduce or eliminate your liability.

CGT Rates and Allowances (current tax year)

For 2026/27, the capital gains tax allowance (annual exempt amount) is £3,000 (check GOV.UK for latest). Above this, capital gains tax rates depend on your income tax band and the type of asset:

Asset type	Basic-rate taxpayer	Higher / additional rate
Shares and most other assets	10%	20%
Residential property (not your main home)	18%	24%
Qualifying business disposals with BADR	10%	10% (up to £1m lifetime)

Your income (including taxable income for the year) is used to determine which band applies. Capital gains tax brackets can effectively push part of your gain into a higher band, so planning matters.

60-day reporting for UK residential property

If you sell UK residential property that is not your main home and capital gains tax is due, you must report the disposal and pay the tax within 60 days of completion using HMRC's UK Property Disposal Service — separately from, and usually before, your Self Assessment return. Missing the 60-day deadline triggers automatic penalties and interest, so landlords and second-home owners should plan for it ahead of completion.

When Do You Pay Capital Gains Tax?

You usually report capital gains on your Self Assessment tax return and pay any capital gains tax due by 31 January after the end of the tax year. For disposals of UK residential property, you may need to report and pay within 60 days using the UK Property Disposal Service. Late reporting can lead to interest and penalties, so it is important to keep records and seek advice if unsure.

How to Calculate Capital Gains Tax

To calculate capital gains tax you need to: (1) work out your gain (sale proceeds minus purchase price and allowable costs); (2) deduct any reliefs and losses; (3) subtract your annual CGT allowance; (4) apply the correct CGT rate to the remaining taxable gain. Our free capital gains tax calculator does this for you and gives an estimate of tax due. For complex situations or corporate gains tax, professional advice is recommended.

CGT Reliefs and Exemptions

Several reliefs can reduce your capital gains tax: Private Residence Relief (main home), Business Asset Disposal Relief (formerly Entrepreneurs’ Relief), Gift Hold-Over Relief, and others. ISA and pension gains are generally exempt. Chattels sold for £6,000 or less may also be exempt. We can help you identify which reliefs apply and how to plan disposals to use your CGT allowance and reliefs effectively.

Who we help with capital gains tax

We advise a range of clients on CGT, including: landlords and property investors selling buy-to-lets or second homes (see our dedicated accountant for landlords service and the 60-day reporting rule above); investors disposing of shares, funds or crypto; and business owners selling all or part of a company who want to claim Business Asset Disposal Relief. Whatever the asset, the goal is the same — an accurate figure, every available relief, and deadlines met.

Our Capital Gains Tax Services

We offer capital gains tax advice, CGT calculation support and planning for individuals and trustees. Whether you need a one-off capital gains tax estimator for a disposal or ongoing advice for multiple assets, we can help. Services include: review of gains and allowable costs; use of losses and reliefs; reporting and payment deadlines; and structuring for future disposals. We serve clients across London and the UK.