Airtel has become the first cellular operator in the city to cross the 3-lakh subscriber base. It has also crossed 5-lakh customer base in Andhra Pradesh. In Chennai, it has added more than one lakh subscribers in less than a year and over 50,000 subscribers in the last two-and-a-half months, while in Andhra circle the service provider has added one lakh customers in the last 100 days, taking its total subscriber base to five lakh.