The England batsman will play in India following his omission from the Test squad for the series against New Zealand, which begins on May 21.
Hales will be available for selection for the Indians??? last league game against Sunrisers Hyderabad on May 17, 2015 subject to the completion of contractual paperwork formalities.
The 26-year-old Hales has represented England in 33 Twenty20 Internationals, with an average of 37.92 and a strike rate of 138.46.
Hales has been cited as a potential England opener by Shane Warne but his Test career has seemingly been put on hold by his IPL call-up.