Paul, thank you prompt reply.
If it is inherited property, your gain will be the difference between the valuation of it at the time of inheritance (and not the cost price paid by your nan) and the sale proceeds.
Say the valuation at inheritance was £30,000 and you sell it for £60,000.
Your gain will be (60,000-30,000) = £30,000.
You would claim gains allowance of £11,000 against this gain and your chargeable gain after allowance becomes (30,000-11,000) £19,000.
CGT rate on this would be 18%, 28% or a combination of both depending on your total taxable income including this gain in the year the gain is realised.
Say your taxable income after personal allowance but before the gain is £20,000. First £11,865 of the gain will be taxed at 18% and the balance £7,135 at 28%.
This will make your total CGT £4,133.50.
I hope this is helpful and answers your question.
If you have any other questions, please ask me before you rate my service – I’ll be happy to respond.