Altice Portugal S.A. (formerly known as PT Portugal) is the largest telecommunications service provider in Portugal. Since 2 June 2015 the company has been a wholly owned subsidiary of Altice, a multinational cable and telecommunications company with a presence in France, Israel, Belgium, Luxembourg, Portugal, French West Indies/Indian Ocean Area, the Dominican Republic, and Switzerland. It currently owns the MEO, Moche and SAPO brands.

The assets in Portugal were sold to Altice in 2015 per request of Oi SA to reduce debt. The African assets were mostly sold for the same reason.

The business group formerly called Portugal Telecom, SGPS, SA was divided into PT Portugal SGPS, SA - a company with assets such as MEO - and PT SGPS, a financial holding company with 25.6% of Oi and with a risk investment valued at approximately 900 million euros - which after May 29, 2015 is called Pharol, with headquarters in Amoreiras Plaza.

The first telephone experiments in Portugal connected Carcavelos to the Central do Cabo in Lisbon, in 1877. In 1882, the Edison Gower-Bell Telephone Company was established in both Lisbon and Porto, to develop the respective telephone service concessions. In 1887, the concession was transferred to APT - The Anglo Portuguese Telephone Company, which lasted until 1968, when the Public Company "Telefones de Lisboa e Porto" (TLP) was created. The Post Office, Telegraphs and Telephones (CTT) operated the telephone service in the rest of the country. For the operation of radiotelegraphy and wireless telephone, a contract with the Marconi's Wireless Telegraphy Company concession was confirmed in 1922. In 1925, the "Companhia Portuguesa Rádio Marconi" (CPRM) was set up and took on all responsibilities of the previous concession.

In 1970, CTT became a Public Company and in 1989, the TLP was transformed into a Limited Company, and was controlled by the State.

Throughout October 1992, the Portuguese government and the Public Service Television Corporation RTP agreed to separate the transmitter network from the rest of the corporation, transferring it to a recently created state-owned company named "Teledifusão de Portugal" (TDP). The purpose of this was to create a nationwide TV broadcasting network available for any TV station in Portugal to request its services. At the time, RTP (a "native" client of TDP) was facing competition for the first time since its creation in the 1950s. SIC required the services of TDP, but TVI decided to create its own transmitter Network (RETI), RTP's monopoly shaken after 35 years.

In 1992, CTT became a Limited Company with public capital and the Comunicações Nacionais, SPGS, SA (CN) was created, a state holding company responsible for the managing of all state participation within the sector, comprising CTT, TLP, CPRM and TDP. That year, the telecommunications operations of CTT were detached with the creation of Telecom Portugal, SA, allowing CTT to dedicate itself to postal services. With this, Portugal's telecommunications network was operated by three operators: TLP in the Lisbon and Porto areas, Telecom Portugal was responsible for the remaining national, European and Mediterranean communications; and Marconi took on international traffic. In 1994, a single national telecommunications operator was created with the combination of the companies within the CN State holding: Portugal Telecom, SA merged into one Telecom Portugal, TLP and TDP.

Portugal Telecom was the only telephone operator in Portugal, being a monopoly, until 1994, when the government gradually reduced its control over the corporation. In 2000, Portugal Telecom became a publicly owned company.