Geographic boundaries of the United States Postal Service (USPS) five-digit ZIP Code areas within Massachusetts, from data from the HERE (formerly Navteq) core map release (streets and related data as of April 2018).

In March 2024, MassGIS modified the boundaries for all ZIP Code areas in Boston based on the U.S. Postal Service's ZIP Code Look Up by Address website. MassGIS also added polygons for ZIP Codes 02199 and 02203.

These ZIP Code boundaries are provided as delivered by HERE (with two minor edits by MassGIS, as discussed below). MassGIS makes no claims to the accuracy of the information in this file. These ZIP Code boundaries do not topologically align with MassGIS' Level 3 parcel data and are frequently revised and subject to change. These boundaries should not be confused with ZIP Code Tabulation Areas (ZCTA) provided by the U.S. Census Bureau.