How Cgt Is Calculated

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Comprehensive Guide: How Capital Gains Tax (CGT) is Calculated in the UK

Capital Gains Tax (CGT) is a tax on the profit you make when you sell (or ‘dispose of’) an asset that has increased in value. Understanding how CGT is calculated is essential for anyone looking to sell property, investments, or other valuable assets. This guide will walk you through the complete calculation process, including allowances, reliefs, and tax rates.

What is Capital Gains Tax?

CGT is charged on the gain (profit) you make from selling certain assets. It’s not the total amount you receive from the sale that’s taxed, but the difference between what you paid for the asset and what you sold it for (after accounting for certain costs and reliefs).

Which Assets Are Subject to CGT?

Most personal possessions worth £6,000 or more (excluding your car) are subject to CGT when sold. Common examples include:

• Property that’s not your main home
• Shares that aren’t in an ISA or PEPs
• Business assets
• Cryptocurrencies
• Antiques, art, and collectibles

How to Calculate Your Capital Gain

The basic calculation for CGT is:

1. Determine the sale proceeds – The amount you received from selling the asset
2. Subtract the acquisition cost – What you originally paid for the asset
3. Subtract allowable costs – Such as improvement costs, selling fees, and professional advice
4. Apply any reliefs – Such as Private Residence Relief for property
5. Subtract your annual exemption – £6,000 for 2023/24 tax year
6. Calculate the tax – Apply the appropriate tax rate to the remaining gain

CGT Allowances and Reliefs

Several allowances and reliefs can reduce your CGT bill:

• Annual Exempt Amount: £6,000 for individuals (2023/24), £3,000 for trusts
• Private Residence Relief: If you’re selling your main home, you usually don’t pay CGT
• Letting Relief: Up to £40,000 if you’ve let out a property that was once your main home
• Business Asset Disposal Relief: 10% tax rate on qualifying business assets (formerly Entrepreneurs’ Relief)
• Gift Hold-Over Relief: Postpone paying CGT when you give away business assets

CGT Tax Rates 2023/24

The tax rate you pay depends on your income tax band and the type of asset:

Asset Type	Basic Rate Taxpayer	Higher/Additional Rate Taxpayer
Residential Property (not main home)	18%	28%
Other Chargeable Assets	10%	20%
Business Assets (with Business Asset Disposal Relief)	10%	10%

Step-by-Step CGT Calculation Example

Let’s work through a practical example to illustrate how CGT is calculated:

Scenario: You bought a buy-to-let property in 2015 for £200,000. You spent £30,000 on improvements and sold it in 2023 for £350,000. Your selling costs were £5,000. You’re a higher-rate taxpayer with no other gains this year.

1. Calculate the gain: Sale price (£350,000) – purchase price (£200,000) – improvement costs (£30,000) – selling costs (£5,000) = £115,000 gain
2. Subtract annual exemption: £115,000 – £6,000 = £109,000 taxable gain
3. Apply tax rate: As a higher-rate taxpayer selling property, you pay 28% CGT
4. Calculate tax due: £109,000 × 28% = £30,520 CGT due

How to Report and Pay CGT

You must report and pay any CGT you owe:

• For property sales, you must report and pay within 60 days of completion
• For other assets, report in your Self Assessment tax return by 31 January following the end of the tax year
• You can report and pay online through the GOV.UK Capital Gains Tax service

Common CGT Mistakes to Avoid

Avoid these frequent errors when calculating CGT:

1. Forgetting to include all costs – Remember to include improvement costs and selling fees
2. Incorrectly calculating the gain – It’s the profit, not the sale price that’s taxed
3. Missing deadlines – Property sales have a strict 60-day reporting requirement
4. Not using your annual exemption – Everyone gets an annual tax-free allowance
5. Ignoring reliefs – Many people miss out on valuable reliefs they’re entitled to

CGT Planning Strategies

Legal ways to reduce your CGT bill:

• Use your annual exemption – Consider selling assets over multiple tax years
• Transfer assets to your spouse – Use both of your annual exemptions
• Invest in an ISA – Gains within an ISA are tax-free
• Time your disposals – Sell in a year when you have lower income to potentially pay a lower rate
• Consider gift hold-over relief – For business assets, you might be able to defer the gain

CGT for Different Asset Types

Property (not your main home)

When selling a second home or buy-to-let property:

• You may qualify for Private Residence Relief if it was ever your main home
• Letting Relief may apply if you lived in the property before letting it
• The tax rate is 18% for basic rate taxpayers, 28% for higher rate

Shares and Investments

For shares not held in an ISA:

• The tax rate is 10% for basic rate taxpayers, 20% for higher rate
• You can use the ‘bed and ISA’ strategy to move investments into an ISA
• Consider using your dividend allowance before selling shares

Cryptocurrency

HMRC treats crypto as an asset for CGT purposes:

• Every crypto-to-crypto trade is a taxable disposal
• You can use the ‘pooling’ method to calculate gains
• Keep detailed records of all transactions

Recent Changes to CGT Rules

The UK government has made several recent changes to CGT:

Change	Effective Date	Impact
Annual exemption reduced from £12,300 to £6,000	April 2023	More people will pay CGT on smaller gains
Annual exemption to reduce further to £3,000	April 2024	Even more taxpayers will be affected
Reporting deadline for property extended from 30 to 60 days	October 2021	More time to report and pay
Business Asset Disposal Relief lifetime limit reduced to £1m	March 2020	Less relief available for business owners

When You Don’t Need to Pay CGT

You don’t usually need to pay CGT when:

• Selling your main home (with some exceptions)
• Selling personal possessions worth £6,000 or less
• Giving assets to your spouse or civil partner
• Selling assets within an ISA or PEPs
• Selling UK government gilts or Premium Bonds
• Making a loss on the sale (though you can use losses to reduce future gains)

Record Keeping for CGT

HMRC requires you to keep records for at least 5 years after the 31 January following the tax year of the disposal. You should keep:

• Dates and details of acquisitions and disposals
• Purchase and sale prices
• Receipts for improvement costs
• Details of any reliefs claimed
• Calculations of gains and losses

CGT and Inheritance Tax

CGT and Inheritance Tax (IHT) can sometimes interact:

• When you inherit an asset, you usually inherit it at its ‘probate value’
• If you later sell the asset, you calculate the gain from the probate value
• Some assets may qualify for both CGT reliefs and IHT exemptions
• The ‘uplift in basis’ rule means beneficiaries don’t pay CGT on gains made before inheritance

International Considerations

If you’re non-UK resident or have assets abroad:

• UK residents pay CGT on worldwide assets
• Non-residents only pay CGT on UK property and certain other UK assets
• Double taxation agreements may prevent you paying tax twice on the same gain
• Different countries have different CGT rules and rates

Professional Advice

Given the complexity of CGT rules, it’s often wise to seek professional advice, especially when:

• Dealing with high-value assets
• You have multiple disposals in a tax year
• You’re unsure about which reliefs apply
• You have international assets
• You’re planning significant financial transactions

A qualified accountant or tax advisor can help you:

• Calculate your CGT liability accurately
• Identify all available reliefs and exemptions
• Plan disposals to minimize tax
• Complete and file the necessary paperwork
• Handle any disputes with HMRC

Important Disclaimer: This calculator and guide provide general information only. They don’t constitute financial or tax advice. CGT rules can be complex and depend on your individual circumstances. For accurate advice tailored to your situation, please consult a qualified tax professional or financial advisor. The information provided is based on UK tax law as of the 2023/24 tax year and may be subject to change.

For official guidance, visit the GOV.UK Capital Gains Tax page or consult ICAEW’s tax resources for professional accountants’ perspectives.