Lake County, Indiana ZIP Codes

27 ZIP Codes

Zip Code
City
Population
46307Crown Point71,673
46410Merrillville39,243
46342Hobart32,224
46312East Chicago26,022
46375Schererville24,188
46321Munster23,733
46322Highland23,680
46311Dyer23,321
46323Hammond23,047
46324Hammond21,409
46356Lowell19,721
46373Saint John18,843
46319Griffith17,847
46303Cedar Lake17,680
46408Gary15,747
46404Gary15,428
46320Hammond14,353
46405Lake Station12,184
46394Whiting11,894
46403Gary10,929
46327Hammond10,597
46406Gary9,001
46407Gary8,577
46409Gary7,184
46402Gary5,836
46376Schneider319
46377Shelby45

Overview of ZIP Codes in Lake County

ZCTAs are geographic areas created by the US Census Bureau to approximate the delivery areas of ZIP Codes for statistical analysis. While ZCTAs use the same five-digit codes as ZIP Codes, they represent defined geographic areas that may not exactly match the mail delivery routes of ZIP Codes.
27
ZIP Codes

The data shown reflect ZCTAs from the US Census. As of 2025, there are 27 ZCTAs in Lake County, Indiana (US Census).