Thank you for your prompt reply.
Capital Gains tax calculation
Main residence (Apr 2011 to Sep 2012) = 18 months
Rented period (Oct 2012 to say Sep 2013) = 12 months
Total period of ownership (18+12) = 30 months
Capital gain say (300,000-240,000) = £60,000
Private residence relief = 18 months
The final three years (36 months) always qualify for relief, even if you weren't living there, as long as it's been your only or main home at some point during the time that you've owned it.
Based on above, all gain would be covered by private residence relief and no CGT payable.
CGT rates are 18%, 28% or a combination of both depending on your total taxable income in the tax year of sale.
I hope this is helpful and answers your question.
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