In the Philippines, a ZIP code is used by the Philippine Postal Corporation (PhlPost) to simplify the distribution of mail.^[1][2] While its function similar with the ZIP Codes used in the United States, its form and usage are quite different. Its use is not mandatory but highly recommended by the PhlPost. A ZIP code is composed of a four-digit number representing a locality. Usually, more than one code is issued for areas within Metro Manila, and a single code for each municipality and each city in provinces, with exceptions such as:^[1]

• Central Luzon State University has its own ZIP code.
• Davao International Airport has its own ZIP code.
• Philippine Military Academy has its own ZIP code.
• University of Mindanao has its own ZIP code.