PLDT was established on November 18, 1928, by a Philippine Government act. By the 1930s, PLDT had an expansive fixed-line network and for the first time linked the Philippines to the outside world via radiotelephone services, connecting the Philippines to the United States and other parts of the world.

In 1967, after selling shares of the company, a group of Filipino businessmen and entrepreneurs led by Ramon Cojuangco became the owner of PLDT. In 1968, PLDT’s main office in Makati (today known as the Ramon Cojuangco Building) was opened and PLDT’s expansion programs began in the hope of bringing reliable telephone service to rural areas.

On March 16, 1988, PLDT launched the country’s first cellular phone system in Sampaloc, Manila to enable the public use of mobile phones. By 1997, the company, through Mabuhay Satellite Corporation, launched the Philippines’ first local communications satellite, Agila II. In April 2016, the company, then known as the Philippine Long Distance Telephone Company, dropped the “long distance telephone” from its corporate name and was renamed PLDT Inc.

It is one of the country’s major telecommunications providers, along with Globe Telecom and startup Dito Telecommunity. Founded in 1928, it is the oldest and largest telecommunications company in the Philippines, in terms of assets and revenues.

The company’s core businesses are fixed-line telecommunications, mobile telephony services, broadband, and internet of things services under various brands. It also has investments in broadcasting, print media, utilities, and direct-to-home satellite services, among others. 

According to Wikipedia