Press Trust of India on Thursday quoted former India and Knight Riders captain Sourav Ganguly as saying that Whatmore would take charge of Kolkata for the IPL's third season next year.
"I was told that Whatmore will be our next coach. It will be exciting to work with him," Ganguly said.
The team has not made an official announcement about a new coach.
Whatmore, who represented Australia in seven test matches, turned into a successful coach when he helped shape Sri Lanka's 1996 World Cup victory. After a short stint with English team Lancashire, he returned to coach Sri Lanka again. He also had a stint as Bangladesh coach and helped it evolve as a cricket-playing nation.
Ganguly was Kolkata's captain in 2008, but was replaced by New Zealander Brendon McCullum this year.