Regions first came to existence on September 24, 1972, when the provinces of the Philippines were organized into eleven regions under Presidential Decree No. 1 as part of the Integrated Reorganization Plan of President
Ferdinand Marcos. Since that time, other regions have been created and some provinces have been transferred from one region to another.
Timeline • June 22, 1973 –
Pangasinan was transferred from Region III (
Central Luzon) to Region I (
Ilocos Region). • July 7, 1975 – Region XII was created, and some regions of
Mindanao are reorganized. • July 25, 1975 – Regions IX and XII were declared as Autonomous Regions in Western and Central Mindanao, respectively. • August 21, 1975 – Region IX was divided into Sub-Region IX-A and Sub-Region IX-B. Some regions in Mindanao are reorganized. • November 7, 1975 –
Metro Manila was created. • January 23, 1976 – Metro Manila was separated from
Southern Tagalog to become Region IV; Southern Tagalog becomes Region IV-A. • June 2, 1978 – Metro Manila was declared the National Capital Region. • June 11, 1978 – The regional center of Region IX was transferred from
Jolo, Sulu to
Zamboanga City. • July 15, 1987 – The
Cordillera Administrative Region was created. • August 1, 1989 – The
Autonomous Region in Muslim Mindanao (ARMM) was created. Region XII reverted to an administrative region. • January 30, 1990 – Residents reject in
a plebiscite the ratification to create the Cordillera Autonomous Region. • October 12, 1990 – Reorganization and/or renaming of the Mindanao regions: Region IX (Western Mindanao), Region X (
Northern Mindanao), Region XI (Southern Mindanao), Region XII (Central Mindanao), and ARMM. Regional center of Region IX is transferred to
Pagadian, with Zamboanga City remaining as the region's commercial and industrial center. • February 23, 1995 – Region XIII (
Caraga) was created and minor reorganization of some Mindanao regions;
Sultan Kudarat is transferred to Region XII. • March 7, 1998 – Residents reject in
a plebiscite for the second time the ratification to create the Cordillera Autonomous Region. • December 18, 1998 – Sultan Kudarat was reverted to Region XII. • March 31, 2001 – The ARMM was expanded. • September 19, 2001 – Most Mindanao regions were reorganized and some are renamed, such as Region IX (
Zamboanga Peninsula), Region XI (
Davao Region), and Region XII (
Soccsksargen). • May 17, 2002 – Region IV-A (
Calabarzon) and Region IV-B (
Mimaropa) were created from the former Region IV (
Southern Tagalog) region;
Aurora is transferred to Region III. • October 28, 2003 –
Calamba, Laguna was designated as the regional center of Region IV-A. • March 30, 2004 –
Koronadal was designated as the regional center of Region XII. • May 23, 2005 –
Palawan was transferred from Region IV-B to Region VI (
Western Visayas). • August 19, 2005 – The transfer of Palawan to Region VI is held in abeyance. • November 22, 2007 –
Calapan is designated as the regional center of Region IV-B. • May 29, 2015 – The
Negros Island Region (NIR) was created.
Negros Occidental and
Bacolod are transferred from Region VI, and
Negros Oriental is removed from Region VII (
Central Visayas). • July 17, 2016 – The Southwestern Tagalog Region (Mimaropa Region) was established comprising the former Region IV-B (in effect merely a renaming and discontinuation of the "Region IV-B" designation since no boundary changes were involved). • August 7, 2017 – The NIR was abolished. Negros Occidental (including Bacolod) and Negros Oriental are reverted to Regions VI and VII, respectively. • January 25, 2019 – The
Bangsamoro Autonomous Region in Muslim Mindanao (BARMM) is created, replacing the ARMM after the ratification of the
Bangsamoro Organic Law. • June 11, 2024 – The NIR was re-established, with
Siquijor transferred from Region VII. • September 9, 2024 –
Sulu was declared not part of the BARMM. • July 30, 2025 – Sulu was reverted to Region IX. == List of regions ==