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How capital gains are taxed

By Ian Robinson

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How capital gains are taxed

There are four steps to working out whether you have made a taxable gain or loss. We explain how to calculate any tax due and what allowances you can claim.

  • Step 1: Start with the final value. This is usually the sale proceeds or the market value if you give the item away.
  • Step 2: Deduct the initial value. This is usually the price you paid or the market value when you were given the item. For anything you have owned since before 31 March 1982, it is the market value on that date.
  • Step 3: Deduct any allowable expenses. These include the costs of buying and selling (for example, dealing costs, stamp duty and advertising). They also include the cost of improving the asset, provided the improvement is reflected in the item’s value.
  • Step 4: If the answer is a loss, you can get tax relief by setting it against gains on other assets either this year or in future.

Now add together all your gains for the year, and deduct any losses and your annual tax-free allowance. For 2017-18, the allowance is £11,300. In 2016-17 it was £11,100.

For sales and gifts you make in 2017-18, whatever remains is taxed at either 10% or 20% depending on your tax band (prior to April 2016, rates were 18% and 28% respectively).

Example capital gains tax calculation for 2017-18
Calculation Amount
Capital gain £20,000
Losses £1,400
Annual allowance £11,300
Taxable gain = £20,000 - £1,400 - £11,300 £7,300 taxable gain
CGT rate 10% tax rate
Capital gains tax payable - £7,500 x 10% £730 payable

Tax relief for losses

You get tax relief for genuine losses when you sell or give away your possessions. First, you deduct losses from any gains you make in the same year. You have to deduct all these losses even if this takes you below your tax-free allowance.

If you still have some losses left, you can carry them forward. But if you still have some gains remaining, you next deduct any losses brought forward from previous years, but only so much as is needed to reduce your gains to the level of your tax-free allowance.

Example calculation of losses for 2017-18
Calculation Amount
Gain from selling second home £50,000
Loss on shares £10,000
Net gains for year are £50,000 - £10,000 £40,000 net gains
Losses carried forward from previous years £65,000
Deduct tax free allowance from the net gain £40,000 - £11,300 = £28,700
Tax free losses left (£65,000 - £28,700) £36,300 left to carry forward
Capital gains tax to pay £0
  • Last updated: April 2017
  • Updated by: Tom Wilson

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