GSM telecom operators added 6.5 million subscribers in April, taking the total user base to 670.57 million.
The GSM subscriber base was 664.08 million in March.
Leading telecom operator Bharti Airtel added 2.01 million users, highest in April, taking its total subscriber base to 183.29 million, according to the data released by the Cellular Operators Association of India (COAI).
It had a market share of 27.33% by April-end.
Aditya Birla group firm Idea Cellular, with 17.03% market share, added 1.48 million new subscribers during the month, taking its subscriber to 114.20 million.
Uninor, which has seen significant growth in user base in the previous months, added 1.12 million new customers in April. Its user base was at 43.55 million by April-end.
Aircel, which had lost customers last month too added 1.01 million new users during the month to take its base to 63.58 million.
Vodafone, with a market share of 22.56% added 0.81 million customers during the month taking its subscriber base to 151.28 million by the end of April.
State-owned telecom firm BSNL did not see any additions during the month. MTNL also lost 0.10 million customers during the month.
The subscriber base of BSNL and MTNL stood at 94.67 million and 5.48 million respectively by the month-end.
Videocom added 0.15 million new customers in the month taking its total base to 6.10 million at the end of April-end.
Operators like Uninor and Videocon, whose licences have been cancelled by the Supreme Court in its February order saw over two per cent growth in their subscriber additions during the month.
Others like S Tel and Etisalat DB did not saw any new user addition. These companies have already announced shutting down of services and are now helping their users move to other operators through MNP.
Sistema Shyam TeleServices (SSTL), which operates under MTS brand and whose licence was also cancelled by the apex court added 0.20 million customers in April taking its total customer base to 16.05 million.