Telefóncia del Sur, the leading telecommunications company in the south of Chile, is a 74.4%-owned subsidiary of Quiñenco.

With more than 317,000 clients, it covers both residential and business clients in the 8th, 9th, 10th and 11th regions of the country, including the cities of Concepción, Temuco, Valdivia, Osorno, Puerto Montt and Coyhaique.

Over the past several years, Telefónica del Sur has been undergoing an important transition from a traditional fixed telephony provider to a multi-product telecommunications operator offering wireless local telephony, Internet (ISP), security services (tele-vigilance) and specialized telecom services for businesses. As of 2008 Telefónica del Sur launched “Uno Móvil”, a new service which combines cellular and wireless telephony in one phone.

During 2008 Telefónica del Sur entered into a strategic alliance with Movistar, that enables Telsur to rent its networks and antennas in order to offer mobile telephone services throughout Chile under its own name, as well as international roaming. Thus, Telefónica del Sur becomes the first Virtual Mobile Operator in the country and in Latin America, and the fourth mobile operator in Chile.

Non-regulated services now make up a significant portion of Telefónica del Sur's revenue base.