The total subscriber base at the end of October was 672.80 million users.
The top three operators Bharti Airtel, Vodafone and Idea Cellular which account for over 67 percent of the GSM market lost over 6.74 million users in November, data released by Cellular Association of India (COAI) said.
Not even a single operator added any new subscriber during November, 2012.
Bharti Airtel, which is the industry leader with a 27.66 percent market share, lost 2.80 million users to take its subscriber base to 183.61 million, it said.
Vodafone and Idea Cellular lost 2.38 million users and 1.56 million users respectively. With this, Vodafone's subscriber base stood at 150.76 million, while that of Idea Cellular was at 114.14 million at the end of November 2012, COAI said.
Aircel lost 1.46 million users in November which squeezed its user base to 65.32 million at the end of November.
Uninor lost 4,37,915 users, while Videocon lost 3,79,787 subscribers in the said month.
The COAI figures showed that state-run operator BSNL did not add a single subscriber in November and had a 14.64 percent share in the GSM market with 97.17 million subscribers.
Another state-run firm MTNL lost 741 users, taking its user base to 5.12 million at the end of November 2012.