Following Scott McDonald, Bevan will be with the Terriers on a one year loan, enabling him to get a real chance of prolonged first team football.
Wadsworth said: "I'm very pleased that we've signed Scott. I have been looking at Scott for a while and he has been in Huddersfield for the past week. "He's a big lad and an excellent goalkeeper.
"With Paul Jones and Neil Moss keeping him out of the Southampton side, a spell at Huddersfield will be very good for Scott's development and the development of Huddersfield Town.
"I feel his appointment will be terrific for Town. He's young and was very eager to come here. At 6ft 6in, it goes without saying that Scott is a very imposing goalkeeper and I have no doubt at all that he is ready to step up to Football League level."
"I know him very well from my time with Southampton. All the staff down there think very highly of him and with the chance to play in the League games, it will do his development no harm.
"It's a great opportunity for him, he's a good lad to have around the place and it's a great opportunity for us to utilise a player who is third in the pecking order at a Premiership club but who is definitely ready to step up."
Goalkeeping coach Dave Watson added: "Scott is a very big lad and he is not scared to come off his line and catch the ball.
"That is something you always look for in a goalkeeper.