Bharti Airtel Limited (NSE: BHARTIARTL, BSE: 532454), commonly known as Airtel, is an Indian telecommunications company that operates in 20 countries across South Asia, Africa and the Channel Islands. It operates a GSM network in all countries, providing 2G, 3G and 4G services depending upon the country of operation. Airtel is the fifth largest telecom operator in the world with over 243.336 million customers across 20 countries as of March 2012. It is the largest cellular service provider in India, with over 183.3 million subscribers at the end of May 2012. Airtel is the third largest in-country mobile operator by subscriber base, behind China Mobile and China Unicom.

Airtel is the largest provider of mobile telephony and second largest provider of fixed telephony in India, and is also a provider of broadband and subscription television services. It offers its telecom services under the airtel brand, and is headed by Sunil Bharti Mittal. Bharti Airtel is the first Indian telecom service provider to achieve Cisco Gold Certification. It also acts as a carrier for national and international long distance communication services. The company has a submarine cable landing station at Chennai, which connects the submarine cable connecting Chennai and Singapore.