Postby maths » Sat Mar 16, 2019 8:52 pm
It seems likely that on moving lock stock and barrel to the UK that your Guernsey property would cease to qualify as your principle residence for CGT. However, on a sale anytime within 18 months of leaving Guernsey no UK CGT charge would arise (as the last 18 months of ownership are effectively deemed to be a period of occupation).
This 18 month period is currently under review and is likely to reduce to 9 months effective 6 April 2020.
After the 18/9 month period a CGT charge would arise on any gain albeit this is initially likely to be minimal.
If you are currently non-UK domiciled and remain so following the move to the UK, any gain arising from a disposal of the Guernsey property which would be chargeable may be deferred assuming the remittance basis applied at that time.