The host nation will be represented in all 26 Olympic sports and are aiming to win more medals in more sports since 1908, with a target of 48 medals set by elite funding agency UK Sport.
In Beijing, Team GB numbered just 313 athletes and they won 47 medals, including 19 golds, to finish fourth on the medal table.
In Athens 270 pulled on British colours, 320 travelled to Sydney and 303 were present in Atlanta.
“With the final athlete selections announced today we are now all set for the delegation registration meeting on Monday," said Team GB chef de mission Andy Hunt.
"This is an important milestone and moment as that is when we officially enter the athletes and support staff selected to represent Team GB – Our Greatest Team – on home soil at the London 2012 Olympic Games.”
The largest squads named are 78 athletes for track and field, 47 for rowing and 44 for swimming while the smallest is the one-strong weightlifting team.