The postal codes in eastern Santiago begin with 7, the postal codes in metropolitan Santiago begin with the number 8 and postal codes in the rest of Santiago begin with the number 9. All Chilean postal codes are seven digits in length.
The municipalities in Santiago that have postal codes beginning with the number 7 include Providencia, Las Condes, Vitacura, Lo Barnechea, Ñuñoa, La Reina, Macul and Peñalolén.
All municipalities in Santiago Province that do not have postal codes that begin with 7 have a postal code that begins with the number 8, along with the municipalities of San Bernardo and Puente Alto.
The rest of Santiago has postal codes that begin with the number 9. This includes the provinces of Chacabuco, Melipilla, Talagante, Maipo (except for San Bernardo) and Cordillera (except for Puente Alto).