• Manila (until 1901) – Incorporated into Rizal; portions around Manila later consolidated to form present-day NCR.
• Lepanto-Bontoc (1902–1908) – Incorporated into Mountain Province.
• Moro Province (1903–1913) – Converted to the Department of Mindanao and Sulu, composed of seven provinces. Now part of several regions in Mindanao.
• Ambos Camarines (1901–1908) – Divided into Camarines Norte and Camarines Sur, although the wording of Act No. 2809 implies Camarines Norte was created from Ambos Camarines, the remainder of which was renamed Camarines Sur. Camarines Sur retained the provincial capital of Nueva Caceres.
• Misamis (1901–1939) – Partitioned into Misamis Occidental and Misamis Oriental. Misamis Oriental retained the provincial capital of Cagayan.
• Mindoro (1902–1950) – Divided into Occidental Mindoro and Oriental Mindoro. Oriental Mindoro retained the provincial capital of Calapan.
• Zamboanga (1914–1952) – Partitioned into Zamboanga del Norte and Zamboanga del Sur. The de jure provincial capital of Molave was placed under the jurisdiction of Zamboanga del Sur which had its capital in Pagadian. Zamboanga Sibugay later created from Zamboanga del Sur.
• Lanao (1914–1959) – Divided into Lanao del Norte and Lanao del Sur. Lanao del Sur retained the provincial capital of Dansalan (now Marawi).
• Surigao (1901–1967) – Partitioned into Surigao del Norte and Surigao del Sur. Surigao del Norte retained the provincial capital of Surigao City and the provincial seal. The province of Dinagat Islands was later created from Surigao del Norte.
• Davao (1914–1967; 1972–1998) – Divided into Davao del Norte, Davao del Sur and Davao Oriental. Davao del Norte was officially known as Davao from 1972 to 1998, when Compostela Valley (now Davao de Oro) was later created from Davao province. Davao Occidental later created from Davao del Sur.
• Agusan (1907–1967) – Partitioned into Agusan del Norte and Agusan del Sur. Agusan del Norte retained the former provincial capital of Butuan. The provincial capital was officially transferred to Cabadbaran in 2000 but the provincial government services and functions are yet to be completely transferred to the new capital.
• Negros del Norte (1985–1986) – Batas Pambansa Blg. 885, which created a new province out of the northern part of Negros Occidental, took effect on December 23, 1985, with a plebiscite to ratify the law held on January 3, 1986. The province comprised the present-day cities of Cadiz (which was to serve as the capital), Escalante, Sagay, San Carlos, Silay and Victorias, as well as the municipalities of Calatrava, Don Salvador Benedicto, Enrique B. Magalona, Manapla, and Toboso. Despite voters ratifying Batas Pambansa Blg. 885, on July 11, 1986, the Supreme Court declared the law and the proclamation of the province null and void. The ruling states the enabling law was unconstitutional for, among other things, not including the rest of Negros Occidental in the plebiscite, and the proposed province not meeting the 3,500 square kilometer land area requirement of the 1983 Local Government Code.

Read more on Wikipedia

When the United States acquired the Philippines from Spain in 1898, the islands were divided into four gobiernos (governments), which were further subdivided into provinces and districts. The American administration initially inherited the Spanish divisions and placed them under military government. As insurgencies were pacified, civil government was gradually organized.

1900–1901
• November 23, 1900 – Civil government of the province of Benguet established through Act No. 49. Capital moved to Baguio.
• February 6, 1901 – Act No. 83, or the Provincial Government Act, enacted by the Philippine Commission.
• February 13 – Provisions of the Provincial Government Act extended to Pampanga through Act No. 85.
• February 16 – Provisions of the Provincial Government Act extended to Pangasinan through Act No. 86. Towns of Balungao, Rosales, San Quintin and Umingan annexed from Nueva Ecija.
• February 18 – Provisions of the Provincial Government Act extended to Tarlac through Act No. 87.
• February 27 – Provisions of the Provincial Government Act extended to Bulacan through Act No. 88. Capital moved to Malolos.
• March 2 – Provisions of the Provincial Government Act extended to Bataan through Act No. 92.
• March 12 – Provisions of the Provincial Government Act extended to Tayabas through Act No. 103. Capital moved to Lucena.
• March 16 – Provisions of the Provincial Government Act extended to Romblon, elevated from Spanish-era status of District, through Act No. 104.
• March 18 – Provisions of the Provincial Government Act extended to Masbate, elevated from Spanish-era status of District, through Act No. 105.
• April 11 – Provisions of the Provincial Government Act extended to Iloilo, formed through the merging of the Spanish-era Province of Iloilo with the Comandancia of Concepcion, through Act No. 113.
• April 13 – Provisions of the Provincial Government Act extended to Antique through Act No. 114.
• April 15 – Provisions of the Provincial Government Act extended to Capiz through Act No. 115.
• April 18 – Provisions of the Provincial Government Act extended to Cebu through Act No. 116.
• April 20 – Provisions of the Provincial Government Act extended to Bohol through Act No. 117.
• April 22 – Provisions of the Provincial Government Act extended to Leyte through Act No. 121.
• April 26 – Provisions of the Provincial Government Act extended to Albay through Act No. 122.

Read more on Wikipedia

• Occidental Leyte and Oriental Leyte (1923) – Leyte was divided into two new provinces by Act No. 3117 on March 27, 1923. The division never took place, however, as no proclamation was issued by the Governor-General.
• Samal (1969) – The sub-province of Samal was created by Republic Act No. 5999 and covered the area of the present-day Island Garden City of Samal. However, the sub-province was never inaugurated.
• Maranaw (1971) – Republic Act No. 6406, which sought to create a new province out of eastern Lanao del Sur (now corresponding to the province's first congressional district), was approved on October 4, 1971. The province was to consist of the municipalities of Bubong, Ditsaan-Ramain (including what is now Buadiposo-Buntong), Kapai, Lumba-Bayabao (including what is now Maguing), Marantao, Masiu, Mulondo, Saguiaran, Piagapo, Poona Bayabao, Tamparan, Taraka and Wao (including what is now Bumbaran), with the chartered city of Marawi serving as the new province's capital. Lanao del Sur was to retain the remaining municipalities, with Malabang serving as its new capital. Section 4 of RA 6406 provided that "The new provinces as provided in this Act shall come into existence upon the election and qualification of their first elective provincial officials, who shall be elected in a special election simultaneously with the general elections of November, nineteen hundred and seventy-three." The division never took place due to the declaration of martial law in the Philippines on September 21, 1972, which disrupted the scheduled general elections for 1973 and paved the way for the adoption of a new Constitution and the establishment of the Fourth Philippine Republic. A legacy of this unimplemented division is the existence of two ZIP code series for Lanao del Sur: the 93- series was retained by what were to be the remaining towns of the province (with Malabang, the new capital, being reassigned the code 9300), while a new series (97-) was assigned to what was supposed to be the province of Maranaw (with Marawi getting the new code 9700).
• Isabela del Norte and Isabela del Sur (1995) – On February 20, 1995, Republic Act No. 7891, which sought to divide the province of Isabela, was approved. Isabela del Norte was to comprise municipalities belonging to the province's first and second congressional districts with Ilagan serving as capital. Isabela del Sur was to consist of the third and fourth congressional districts (excluding the independent component city of Santiago), with Cauayan as the capital. The proposed division was rejected in a plebiscite held on June 20, 1995.
• Quezon del Norte and Quezon del Sur (2007) – The act dividing the province of Quezon into two, Republic Act No. 9495, lapsed into law without the President's signature on September 7, 2007. Quezon del Norte (which would be renamed from Quezon) was to be composed of the first and second congressi…

Read more on Wikipedia