The 24-year-old has made seven appearances for Barclays Premier League Rangers so far this term, most recently during the 1-0 defeat at Arsenal on New Year's Eve, and arrives at the Madejski Stadium in search of regular first-team football.
No recall clause has been inserted into the deal, and Reading manager Brian McDermott was delighted with his latest acquisition.
He told the Royals' official website: "He can play anywhere in the back four and we think this is a really good signing.
"He's played a number of games in the Premier League this year and played more than 30 times with Kaspars (Gorkss, the Reading centre-back) last year.
"I remember him as a youngster at Arsenal, Bournemouth, he's been a utility player and he's just the job at 24."