The top three operators - Airtel, Vodafone and Idea - which account for over 67 per cent of the GSM market lost over 2.17 million users in September, according to the data released by COAI. However, Aircel and Uninor added subscribers to cushion the impact on industry somewhat.
Bharti Airtel, which is the industry leader with a 27.68 per cent market share, lost 0.98 million users to take its subscriber base to 185.92 million, it said.
Idea Cellular and Vodafone lost 0.5 million users and 0.68 million users respectively. With this, Idea Cellular's subscriber base stood at 115.46 million, while that of Vodafone was at 152.66 million at the end of September 2012,
Loop Mobile lost 47,013 users, while Videocon lost 325,818 subscribers in the said month.
Aircel and Uninor were the only operators that witnessed growth. While Aircel added 655,117 new users, Uninor added 32,662 new subscribers in September, COAI said.
The COAI figures showed that state-run operator BSNL did not add a single subscriber in September and had a 14.33 per cent share in the GSM market with 96.28 million subscribers.
Another state-run firm MTNL lost 14,756 users, taking its user base to 5.1 million at the end of September 2012.
In August, GSM operators had lost over 7.1 million subscribers, out of which 5.1 million opted out of the networks of Bharti Airtel, Vodafone and Idea Cellular.