It was thought that Zara Dampney and Shauna Mullin would only be involved in the women's competition but Steve Grotowski and John Garcia Thompson will now also line up on Horse Guards Parade this month.
The pair have struggled through the qualifying campaign without any funding and minimal sponsorship, only just managing to play the 12 events required to be even considered for a place at the Games.
But their form was considered superior to domestic rivals Greg Weaver and Jody Gooding and they couldn't be happier.
“For an athlete, there is nothing better than being selected to compete at an Olympic Games," said Garcia Thompson.
"It really is a dream come true, and we have been training hard and making real progress. Being selected to Team GB is a real honour, and it is fantastic for my family to be able to come and watch me compete."