As from today a list of Countries have been published where travellers are exempt from self isolating on your return to the UK and the FCO has updated its global advisory against ‘all but essential’ travel, exempting destinations that no longer pose an unacceptably high risk for British travellers.
Further details can be found here regarding Foreign Office advice and for information regarding the countries where you do not require to self isolate on your return can be found here however as there still may be requirements or restrictions when entering certain countries it is important that you read the Travel Advice for your destination.