On November 14, 1935, the Philippine Congress approved the franchise of Philippine Aerial Taxi Company Incorporated to provide mail, cargo and passenger service particularly in the island of Luzon. However, the company became dormant for six years on its scheduled passenger operation under its assigned routes. On February 26, 1941, Philippine Air Lines, Inc., was formally incorporated by a group of businessmen headed by Andrés Soriano. At that time, he was hailed as one of the Philippines' leading industrialists and served as the general manager. He, and former Senator Ramón Fernández, who would become the future chairman and president, acquired the franchise of Philippine Aerial Taxi Company Incorporated, transforming it into the new Philippine Airlines. The airline’s first flight took place on March 15, 1941 with a single Beechcraft Model 18 (NPC-54) on daily services between Manila and Baguio. It carried two pilots and five passengers on its maiden flight. 

PAL services were interrupted during World War II, which lasted in the Philippines from late 1941 to 1945. Upon the outbreak of the Pacific War on December 8, 1941 the two Model 18s were put into military service. On February 15, 1946, PAL resumed operations after a five-year hiatus with service to 15 domestic points with five Douglas DC-3s . Philippine Airlines returned to its original home, the Nielson Field in Makati. The airport, heavily damaged during the war, was refurbished and modernized by PAL. The airport was operated by Manila International Air Terminal, Inc., a wholly owned PAL subsidiary.

On July 31, 1946, PAL became the first Asian airline to cross the Pacific Ocean when a chartered Douglas DC-4 ferried 40 American servicemen to Oakland, California from Nielson Airport. A regular service between Manila and San Francisco started in December 1946. During this time, the airline was designated as the country’s flag carrier. PAL commenced service to Europe in 1947 with the acquisition of more Douglas DC-4s to Rome and Madrid, thus earning the distinction of being the first airline in Southeast Asia to fly to Europe. Each flight took two days with stops at Calcutta, Karachi and Cairo. By the end of the year, the service was extended to London.

By 1948, PAL had absorbed the only other scheduled airlines in the Philippines, Far Eastern Air Transport and Commercial Air Lines. In 1951 PAL leased a DC-3 named "Kinsei" to Japan Airlines, which led to the founding of the country's own national airline. In 1951, Service to Taipei starts with the DC-3. In 1952, The first Douglas DC-6B is delivered, and inaugurate service to Zurich and Frankfurt.

In March 1954, the Philippine government suspended all flights to Europe, Japan and the United States, only to resume five years later. In three years PAL started services to Hong Kong, Bangkok, and Taipei using Convair 340s that would later be replaced by the Vickers Viscount 784, which brought the airline into the turboprop age.

In the 1960s, PAL entered the jet age, initially with a lone Boeing 707, later replaced with Douglas DC-8 aircraft leased from KLM Royal Dutch Airlines in 1962, used for long-haul international flights to Europe and the United States. The DC-3 remained the mainstay of domestic services as it expanded to a total of 72 points as airports were improved or opened, however the robustness of the DC-3 was ideal for these airfields. In 1966, PAL commenced its first jet services to Cebu, Bacolod, and Davao using the BAC1-11. In addition, PAL was also privatized, as the Philippine government relinquished its share in PAL.

A year after the declaration of martial law in 1972, Ferdinand Marcos, during his second presidential term, implemented a monopolizing decree of a one-airline policy. PAL was the lone surviving airline, absorbing Air Manila and Filipinas Orient Airways. On March 10, 1973, PAL was re-designated as the national flag carrier. PAL continued its expansion with the arrival of its first Douglas DC-10 in July 1974. Three years later, the Philippine government re-nationalized PAL, with the Government Service Insurance System holding a majority of PAL shares. 

On April 4, 2012, San Miguel Corporation bought a 49-percent stake in Philippine Airlines for $500 million as part of a strategy to move away from its beer and food businesses. San Miguel, one of the Philippines' biggest conglomerates, said it planned to help modernise and strengthen PAL, renew its aging fleet and restore its competitiveness in the Asian aviation industry. PAL's first major initiative under San Miguel ownership was, on August 28, 2012, an order for 54 Airbus aircraft, comprising 44 Airbus A321 (34 with sharklets and 10 A321neo) and 10 Airbus A330-300. PAL took delivery of its first aircraft under this order in 2013. 

Under San Miguel's management, PAL embarked on expanding its route network, involving both adding new and restoring previously terminated routes. In 2013, the airline announced its return to Abu Dhabi, Dammam and Riyadh, and launched new routes to Brisbane and Perth, as well as Doha and Jeddah. In 2013, PAL was removed from the EU aviation blacklist after three years of negotiations, and the carrier immediately announced its European plans, it launched flights between Manila and London Heathrow to commence in November 2013, its first European destination in 15 years. On October 23, 2014, Philippine Airlines announced the appointment of Bautista as the new President and COO of Philippine Airlines. Under Bautista's rule, Philippine Airlines deferred the deliveries of the Airbus A321neo that was supposed to be delivered from November 2017. Jaime Bautista also announced plans to replace its A340 fleet, with the choice of a new and modern Airbus A350 XWB or Boeing 787 Dreamliner. In addition to new aircraft, PAL has chosen to lease more 777's for its growing long haul flights. 

In March 2015, on the 74th anniversary of the carrier, Philippine Airlines resumed flights to New York City via the John F. Kennedy International Airport with a stopover in Vancouver from Manila, originally utilized the Airbus A340 for its flights, but in October 2015, PAL upgraded to the larger Boeing 777-300ER to increase seat capacity. In addition, Philippine Airlines expanded to the Oceania region by introducing flights to Auckland, New Zealand (via Cairns, Australia) and Port Moresby in Papua New Guinea. In 2016, Philippine Airlines announced the launching of flights between Manila and Doha, Manila and Kuwait City (via Dubai), and Cebu City to Los Angeles. Also in 2016, PAL acquired six Airbus A350-900, it will operate the aircraft on non-stop flights to the U.S. and Europe. On January 1, 2017, Philippine Airlines launched its first international destination from Clark, Pampanga to South Korea's capital Seoul. 

On December 16, 2017, Philippine Airlines took delivery of its 9th Boeing 777-300ER to serve PAL's long haul routes in the United States. The airline also launched its non-stop flights to Toronto. On February 13, 2018, Philippine Airlines, continuing its fleet modernization program, expected delivery of fifteen aircraft for 2018, the first Airbus A350-900s, plus six Airbus A321neos, and 5 Bombardier Q400 next generation planes. 

From June 1, 2018, the airline increased flights to Melbourne from three to five times a week, using the reconfigured Airbus A330s. On The other side in April 2018, it suspended flights to Kuwait due to low demand. It also suspended flights from and to Jeddah, Saudi Arabia. On September 18, 2018. Chorus Aviation and PAL signed a leasing agreement for 3 more Bombardier Q400s. The first non-stop commercial service Manila-New York using an Airbus A350 was launched in October the same year.

History source: Wikipedia.org + Philippineairlines.com