Yes - you are exempt from CGT for 12 months after you vacate the property as your PPR whether you rent it or not. After that CGT becomes an issue. If you lived in the property for 5 years, rent it out for 3 and then sell it then (3-1)/(5+3) = 2/8 = 25% of any gain (less allowances and expenses) is subject to 20% CGT. If you rent the property out within five years of purchase as an owner occupied PPR then a clawback of stamp duty applies. Does that clarify matters? If in doubt get independent, professional advice.