How to Calculate Capital Gains Tax

The amount of capital gains tax you pay will depend on a number of factors, including your income, the type of asset in question, when the asset was disposed and whether any exemptions or reliefs apply.

Below we look more closely at chargeable assets and how to calculate capital gains tax based on your particular level of income.

What is Capital Gains Tax?

Capital gains tax (CGT) becomes payable when an individual, sole trader, partnership or trusts sells a chargeable asset. Assets caught by CGT include non-primary residential property, a business, shares or specific items that have appreciated in value.

Importantly, it is the gain, or profit, you make on disposing of the chargeable asset that is taxed, not the overall amount of money you receive having sold that asset.

Chargeable assets explained

Although an individual’s primary residence is exempt from capital gains tax under what’s known as private residence relief, any property that is not your only or main residence will be classed as a ‘chargeable asset’.

This means that any second home, holiday home, buy-to-let or business property will all be potentially liable to capital gains tax in the event that you make any money on these assets when you come to sell.

Capital gains tax is also payable on assets other than land or buildings. In particular, a chargeable asset can include:

  • personal possessions worth £6,000 or more, such as jewellery or artwork.
  • shares that are not in an ISA or PEP.
  • business assets, such as plant and machinery or fixtures and fittings.

Your car is excluded from personal possessions as this is classed as a ‘wasting asset’ with a predicted useful life of less than 50 years.

Tax-free allowance for capital gains

You are not liable to capital gains tax if all your gains in one year fall below your tax-free allowance. For 2020/21 your individual tax-free allowance is £12,300.

The current annual exempt amount for trustees is £6,150.

The net effect is that if the profit made on the sale of a chargeable asset does not exceed the relevant threshold, there will be no tax to pay for that year. However, you must take into account your overall gains for any given tax year.

Current capital gains tax rates

Capital gains tax is charged at various rates where the applicable rate will be determined by the type of asset disposed of and your total taxable income.

For basic rate taxpayers you will pay the following standard rate of CGT:

  • On residential property 18%
  • On other chargeable assets 10%

For higher rate taxpayers you will pay the following enhanced rate of CGT:

  • On residential property 28%
  • On other chargeable assets 20%

If you pay basic rate tax on your income, you will pay capital gains tax at the standard rate up to an amount of gain equal to your unused income tax basic rate band, and at the higher rate on any excess.

If you pay higher rate income tax, you will pay capital gains tax at the higher rate on the entirety of any profit acquired from a chargeable asset.

How to calculate capital gains tax

The starting point in how to calculate capital gains tax is to work out any taxable gain, ie; any profit made on the disposal of the asset(s) in question.

Broadly speaking, you will deduct the purchase price from the selling price. If the asset was a gift, you will instead need to ascertain the market value of the asset at the time it was bequeathed to you.

All profits made on chargeable assets during any given tax year will need to be added together to give your overall net gains for that year, having deducted any allowable costs as well as your tax-free allowance.

These net gains are then added to your total taxable income to determine the appropriate rate of tax.

Where the two figures combined are above the higher tax threshold, you pay the basic-rate on the part up to the threshold, and the higher rate on the remainder.

Deducting costs from any chargeable gains

When working out how to calculate capital gains tax you will need to know what costs can be deducted from your overall chargeable gain.

The type of allowable expenses that can be deducted will depend on the asset in question. By way of example, for the sale of a property, you will be able to deduct costs incurred in disposing of the property, such as any stamp duty, legal fees, as well as estate agents’ fees.

How to mitigate any capital gains tax liability

Once you have worked out how to calculate capital gains tax, you can then go on to consider how to mitigate your liability.

Needless to say, you will have already deducted the tax-free CGT allowance from any profit made. However, there are other ways to reduce the level of chargeable gains in any given tax year.

In particular, you can use your tax-free allowance against the gains that would be charged at the highest rates, for example, where you would be liable to pay 28% on residential property.

With forward planning and professional advice, it may also be possible to offset any losses from previous years against any gains made in subsequent years.

A tax specialist can additionally advise on any tax reliefs that may be available to you, for example, business asset rollover relief where you use the proceeds from the sale of business assets to buy new assets. Here, any liability to capital gains on the original asset only becomes payable when the new asset is sold.

Deferring your tax liability in this way can be beneficial where your tax-free allowance has been exceeded for that year.

How to calculate capital gains tax for non-UK domiciled

There are special rules in relation to capital gains tax where you are a UK resident but not domiciled in the UK.

If you are non-domiciled in the UK and you pay tax on the remittance basis, you will only be liable to pay capital gains tax on any foreign income and gains that are brought to the UK. However, you will lose your tax-free allowances.

Further, if you are not resident in the UK but own UK residential property, you will be liable to pay non-resident capital gains tax.

How to calculate any capital gains tax in time

Any capital gains will need to be declared by way of a self-assessment tax return and paid within the relevant timeframe.

Any capital gains tax payable will usually fall due by 31 January after the end of the tax year in which the disposal occurred. Alternatively, if you are a UK resident, you can use the ‘real time’ Capital Gains Tax service to report and pay any capital gains straight away.

If you are a non-resident and you have sold a residential property in the UK, you will need to tell HMRC within 30 days. Similar provisions will apply to UK residents for disposals of residential property made on or after 6 April 2020.

Key takeaway on how to calculate capital gains tax

How to calculate capital gains tax is not necessarily straightforward. The rules on capital gains can be complex, not least where numerous assets are disposed of across a number of years, some resulting in losses, others making profit.

However, once you understand how to calculate capital gains tax, you can begin to take full advantage of all available allowances and reliefs to help maximise the benefits and minimise your tax bill.

Legal disclaimer

The matters contained in this article are intended to be for general information purposes only. This article does not constitute tax, financial or legal advice, nor is it a complete or authoritative statement of the rules and should not be treated as such.

Whilst every effort is made to ensure that the information is correct, no warranty, express or implied, is given as to its accuracy and no liability is accepted for any error or omission.

Before acting on any of the information contained herein, expert tax, financial, legal or other advice should be sought.

How to Calculate Capital Gains Tax 2
Taxoo is a leading business and financial resource aimed at supporting businesses by providing reliable information and resources that can save business owners time and money.

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