The Ireland international has made 30 appearances for his country and joins from Championship side Reading
Ireland international Simon Cox has joined League One side Southend United on a two-year deal, the club announced today.
Cox moves from Championship side Reading last season after making just 13 appearances for the club.
"It's a fantastic signing, I can't thank the Chairman enough for this deal, I'm very hopeful that someone of Simon's pedigree will replace Jack Payne's goals," Southend boss Phil Brown told the club's official website.
"I've been working hard & long to pull this signing off and I can't thank the Chairman enough for pushing this through, it's a real coup for the Club."
The 29-year-old has made 30 appearances for the national team and scored four times, but didn't make the Ireland squad for this summer's European Championships.