Empresa Nacional de Telecomunicaciones is engaged in the provision of telecommunication services. Services provided include local, domestic and international long-distance calls, international direct dialing, international directory assistance, international business toll-free service, mobile maritime service via satellite, video conference, international telephone cards, bank credit cards, collect calls, television and radio transmission services, and private corporate networks through a digital network offering voice, data, fax, image and internet services.

Telefonica Brasil is a holding company. Through its subsidiaries and associated companies, Co. is engaged throughout Brazil in rendering Fixed Switched Telephone Service Concession Arrangement ("STFC"); Multimedia Communication Service ("SCM", data communication, including broadband internet); Personal Mobile Service ("SMP"); and Conditioned Access Service ("SEAC" - Pay TV) by means of DTH (a satellite technology), IPTV and cable technologies. Co.'s broadband accesses with speeds higher than 34 Mbps in the state of SAPSo Paulo. Co.'s commercial distribution network (marketed under the Vivo brand), as of Dec 31 2017, consisted of 295 own sales outlets throughout Brazil.