do we need a return ticket if we get visit visa

[shahbazali]

my parents got family visit visa of 6 months. do they need to get return ticked or they can travel on one way ticket as well. they are travelling from pakistan
thanks

[mulderpf]

Generally yes or their visa might be cancelled at the border. Why would you want to get singles in any case as it is generally much cheaper buying one return, rather than two singles.