Buoyed by declining prices of mobile phone handsets, GSM wireless operators are estimated to have added 7.7 million subscribers in September -- the highest ever net addition in a month, surpassing the 7.6 million in March this year.

According to the latest data released by the Cellular Operators' Association of India, GSM operators in the country, excluding Reliance Telecom (the GSM arm of Reliance Dhirubhai Ambani Group's Reliance Communications [Get Quote]), added 7.3 million subscribers last month to take the total to 233.3 million.

The association estimates that Reliance Telecom added at least 370,000 subscribers in the month, which was the number it added in August, shoring up the net additions in September to 7.3 million.

"We are delighted to announce a pre-Diwali GSM bonanza of another record-breaking level of subscriber additions in September 2008. It is estimated that the month's GSM additions would be about 7.7 million when all figures come in," said COAI Director-General T V Ramachandran.

Sunil Bharti Mittal's Bharti Airtel [Get Quote] retained the top rank with a market share of 33.21 per cent and a total user base of 77.48 million. The company added 2.7 million users in September, an increase of 3.61 per cent over its 74.78 million users reported in the previous month.

Vodafone-Essar added 1.87 million and maintained a market share of 23.41 per cent. The company's total subscriber base in the month stood at 54.62 million.

State-owned Bharat Sanchar Nigam Ltd, which operates pan-India operations except in Delhi and Mumbai, and Mahanagar Telecom Nigam Ltd, which operates in Delhi and Mumbai, continued to take a beating from the private operators.

Both witnessed further declines in their market shares. BSNL's fell from 17.06 per cent in August to 16.79 per cent in September as it added 676,000 users, taking its total to over 39 million. The market share of MTNL [Get Quote] declined to 1.58 per cent from 1.61 per cent in August.