#2 ATK - 1.09 million
Kolkata is widely considered to be the home of Indian football, and as the only ISL club from the "City of Joy", ATK deserve a top standing on this list. However, the Red and Whites' 1.09 million followers on Facebook is still shy of the numbers accumulated by the leader. That said, ATK are the most successful ISL club and they haven't been left behind in off-the-pitch matters as well.
The Kolkata-based club are set to gain enormous increments to their social media following, considering they spent heavily on the signing of the legendary Robbie Keane earlier this summer. Whether Keane delivers on the pitch or not remains to be seen, but he will surely improve the club's social media numbers by the end of the 2017-18 ISL.