Call Districts of the Philippines DUのコールエリア・プリフィックス

District No. 1
   NCR – National Capital Region
   Region IV-A – CALABARZON: Cavite, Laguna, Batangas, Rizal, and Quezon
   Region IV-B – MIMAROPA: Occidental Mindoro, Oriental Mindoro, Marinduque, Romblon and Palawan

District No. 2
   Region I – Ilocos Region
   Region II – Cagayan Valley
   CAR – Cordillera Administrative Region

District No. 3
   Region III – Central Luzon

District No. 4
   Region V – Bicol Region

District No. 5
   Region VIII – Eastern Visayas

District No. 6
   Region VI – Western Visayas

District No. 7
   Region VII – Central Visayas

District No. 8
   Region IX – Zamboanga Peninsula
   Region XII – SOCCSKSARGEN: South Cotabato, Cotabato, Sultan Kudarat, Sarangani and General Santos City

District No. 9
   Region X – Northern Mindanao
   Region XI – Davao Region
   Region XIII – Caraga
   ARMM – Autonomous Region in Muslim Mindanao

Sources:
http://ntc.gov.ph/laws/officeorder/1355885017_OO%20108-12-2012.pdf

http://en.wikipedia.org/wiki/Regions_of_the_Philippines
(Wikipedia "Regions of the Philippines")

Map of Regions and Provinces of the Philippines

© Eugene Alvin Villar, 2003.