ARMM (Autonomous Region in Muslim Mindanao)

PSGC: 150000000
ISO: 14
Regional Centre: Cotabato City
Congressional Districts: 8
Provinces: 6
Cities: 2 *
Municipalities: 113
Barangays: 2,470 *

August 1, 1989: ARMM (Autonomous Region in Muslim Mindanao) created from Sulu and Tawi-Tawi from Region IX (Western Mindanao), and Lanao del Sur and Maguindanao from Region XII (Central Mindanao) by Republic Act No. 6734.
September 19, 2001: Basilan transferred from Region IX (Western Mindanao) by Executive Order No. 36.

* Excluding Cotabato City and Isabela, City of.

PSGC: 150700000
ISO: BAS
Province Capital: Isabela, City of
Area Code: 62
Congressional Districts: 1
Cities: 2
Municipalities: 11
Barangays: 255

December 27, 1973: Basilan province created from Zamboanga del Sur by Presidential Decree No. 356.

PSGC: 153600000
ISO: LAS
Province Capital: Marawi City
Area Code: 63
Congressional Districts: 2
Cities: 1
Municipalities: 39
Barangays: 1,158

May 22, 1959: Lanao del Sur province created from Lanao by Republic Act No. 2228.
October 4, 1971: Maranaw province with Marawi City as capital, created from Lanao del Sur by Republic Act No. 6406, but never implemented.

¹ Part of Maranaw.
² Maranaw capital.
³ Lanao del Sur (new) capital after the creation of Maranaw.

PSGC: 153800000
ISO: MAG
Province Capital: Shariff Aguak (Maganoy)
Area Code: 64
Congressional Districts: 1
Cities: 1
Municipalities: 22
Barangays: 316

November 22, 1973: Maguindanao province created from Cotabato by Presidential Decree No. 341.

* Under Muslim Mindanao Autonomy Act No. 201, the lone district of Shariff Kabunsuan also included Cotabato City. COMELEC Resolution No. 7845 dated March 29, 2007, stated that Cotabato City comprised the first congressional district of Maguindanao. COMELEC Resolution No. 7902 dated May 10, 2007, stated that Cotabato City is included under the lone district of Shariff Kabunsuan. The constitutionality of the latter COMELEC resolution was questioned but has found to be constitutional by the Supreme Court in its decision of G.R. No. 177597 and G.R. No. 178628 on July 16, 2008.

PSGC: 158400000
ISO: -
Province Capital: Kabuntalan (Tumbao) *
Area Code: 64
Congressional Districts: 1
Cities: 0
Municipalities: 11
Barangays: 210

October 28, 2006: Shariff Kabunsuan province created from Maguindanao by Muslim Mindanao Autonomy Act No. 201.
July 16, 2008: The Supreme Court in the decision of G.R. No. 177597 and G.R. No. 178628 declares void Muslim Mindanao Autonomy Act No. 201 stating that it is unconstitutional (the law is contrary to Section 5, Article VI, Section 20, Article X and Section 3, Ordinance of the 1987 Constitution) for the ARMM Regional Assembly to create either provinces or cities as this implies creating new seats in the House of Representatives, the power of which only Congress has.

* Some sources give Datu Odin Sinsuat (Dinaig) as the capital.

PSGC: 156600000
ISO: SLU
Province Capital: Jolo
Area Code: 68
Congressional Districts: 2
Cities: 0
Municipalities: 19
Barangays: 410

1878: Jolo created as a district.
July 23, 1914: Sulu province created from the Department of Mindanao and Sulu.
March 10, 1917: Province established by Act No. 2711.

PSGC: 157000000
ISO: TAW
Province Capital: Bongao
Area Code: 68
Congressional Districts: 1
Cities: 0
Municipalities: 11
Barangays: 203

September 11, 1973: Tawi-Tawi province created from Sulu by Presidential Decree No. 302.