what is the last 4 digits of a zip code called
ZIP Code In 1983, the U.S. Postal Service introduced an expanded ZIP Code system that it called ZIP+4, often called "plus-four codes", "add-on codes", or "add-ons". A ZIP+4 Code uses the basic five-digit code plus four additional digits to identify a geographic segment within the five-digit delivery area, such as a city block, a group of apartments, an individual high-volume receiver of mail, a post office box, or any other unit that could use an extra identifier to aid in efficient mail sorting and delivery. But initial attempts to promote universal use of the new format met with public resistance and today the plus-four code is not required.[5] In general, mail is read by a multiline optical character reader (MLOCR) that almost instantly determines the correct ZIP+4 Code from the address—along with the even more specific delivery point—and sprays an Intelligent Mail barcode (IM) on the face of the mail piece that corresponds to 11 digits—nine for the ZIP+4 Code and two for the delivery point.
List of ZIP codes in the Philippines In the Philippines, the Philippine ZIP code is used by the Philippine Postal Corporation (Philpost) to simplify the distribution of mail. While in function it is similar to the ZIP code used in the United States, its form and usage are quite different. The use of ZIP codes in the Philippines is not mandatory, however it is highly recommended by Philpost that they be used. Also, unlike American ZIP codes, the Philippine code is a four-digit number representing two things: in Metro Manila, a barangay within a city or city district (as in the case for Manila), and outside Metro Manila, a town or city. Usually, more than one code is issued for areas within Metro Manila, and provincial areas are issued one code for each town and city, with some rare exceptions such as Dasmariñas, which has three ZIP codes (4114, 4115, and 4126) and Los Baños, which has two ZIP codes (4030 and 4031 for the University of the Philippines Los Baños).