Every ZIP code in the United States, with weather, radar, trivia and the numbers behind it. Five digits since 1963!

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zipcodes.pro — STATE/IN/COUNTY/LAKE

Lake County, IN ZIP codes

There are 32 ZIP codes in Lake County, IN, in 19 towns, from 46303 to 46411. The largest are 46307 (Crown Point), 46410 (Merrillville) and 46342 (Hobart). 1 more crosses into it from a neighbouring county: 46341.

The county seat is Crown Point.

ZIP codes
32
Partly in it
1 more
Towns
19
County seat
Crown Point
County FIPS
18089
State
Indiana
Population
500,379
Median household income
$71,493
Land area
499 sq mi
Area code
219

Lake County ZIP codes by town

Crown Point (county seat)
46307, 46308

Each ZIP code is listed under the county most of its land lies in and the town the Postal Service names it for; a ZIP code's own page shows exactly how it is split.

ZIP codes partly in Lake County

This ZIP code lies mostly in a neighbouring county but covers a twentieth or more of Lake County.

Map of Lake County ZIP codes

4630346307463084631146312463194632046321463224632346324463254632746342463554635646373463754637646377463944640146402464034640446405464064640746408464094641046411

The ZIP codes of Lake County, shaded. Outlines are Census ZIP Code Tabulation Areas (2020), which approximate the mail routes; PO-box and single-address codes have no area and are not drawn. Click any area to open its ZIP code.

Lake County in numbers

About 500,379 people live in Lake County, in 195,130 households, the 2nd most populous of Indiana's 92 counties. The median household income is $71,493 a year, about the same as the Indiana median of $71,957 (US: $80,734). The median owner-occupied home is valued at $230,600 (6% above the Indiana median), and median gross rent is $1,131 a month. The median age is 39.7; 25.8% of adults 25 and over hold a bachelor's degree or higher (29.5% across Indiana); the average commute takes 29 minutes.

Population500,379Lake500,379
Households195,130Lake195,130
Median age39.7Lake39.7Indiana38.1US 38.9
Median household income$71,493Lake$71,493Indiana$71,957US $80,734
Median home value$230,600Lake$230,600Indiana$218,200US $332,700
Median gross rent$1,131Lake$1,131Indiana$1,062US $1,413
Bachelor's degree or higher25.8%Lake25.8%Indiana29.5%US 35.7%
Mean commute28.5 minLake28.5 minIndiana24.1 minUS 26.4 min
Population density1,003 / sq miLake1,003 / sq mi

U.S. Census Bureau, American Community Survey 2020–2024 5-year estimates. Survey estimates carry margins of error, wider for small places. Sources and methods.

Largest towns in Lake County

Largest towns in Lake County
TownZIP codesPopulation
Hammond 5 76,768
Gary 8 68,113
Merrillville 2 36,476
Crown Point 2 34,393
Schererville 1 29,701
Hobart 1 29,558
East Chicago 1 26,022
Munster 1 23,733
Highland 1 23,680
St. John 1 22,567
Dyer 1 16,400
Griffith 1 16,273
Cedar Lake 1 15,295
Lake Station 1 13,185
Lowell 1 11,073

Population of the census place of that name where there is one, otherwise of the ZIP codes the Postal Service addresses by it. A town's ZIP codes can reach past the county line.

Neighbouring counties

Counties that share a ZIP code with Lake County.

Not sure you are in Lake County? What county am I in? answers from your location, near a county line included.

Every ZIP code in Lake County, with figures

ZIP codes in Lake County
ZIP City Type Population Median income Median home
46303 Cedar Lake , IN Standard 17,680 $84,211 $293,500
46307 Crown Point , IN Standard 71,673 $107,800 $324,100
46308 Crown Point , IN No street area — — —
46311 Dyer , IN Standard 23,321 $116,652 $331,600
46312 East Chicago , IN Standard 26,022 $42,125 $105,400
46319 Griffith , IN Standard 17,847 $74,662 $203,300
46320 Hammond , IN Standard 14,353 $37,158 $135,000
46321 Munster , IN Standard 23,733 $110,187 $334,300
46322 Highland , IN Standard 23,680 $78,062 $233,300
46323 Hammond , IN Standard 23,047 $59,688 $166,400
46324 Hammond , IN Standard 21,409 $63,052 $158,800
46325 Hammond , IN No street area — — —
46327 Hammond , IN Standard 10,597 $47,288 $142,100
46342 Hobart , IN Standard 32,224 $75,521 $213,000
46355 Leroy , IN No street area — — —
46356 Lowell , IN Standard 19,721 $89,217 $281,500
46373 Saint John , IN Standard 18,843 $127,146 $408,900
46375 Schererville , IN Standard 24,188 $93,160 $315,400
46376 Schneider , IN Standard 319 $64,205 $187,500
46377 Shelby , IN Standard 45 $38,958 —
46394 Whiting , IN Standard 11,894 $66,176 $173,200
46401 Gary , IN No street area — — —
46402 Gary , IN Standard 5,836 $33,529 $85,400
46403 Gary , IN Standard 10,929 $45,991 $177,600
46404 Gary , IN Standard 15,428 $42,256 $95,200
46405 Lake Station , IN Standard 12,184 $60,881 $139,200
46406 Gary , IN Standard 9,001 $35,839 $91,700
46407 Gary , IN Standard 8,577 $28,526 $60,200
46408 Gary , IN Standard 15,747 $47,453 $102,600
46409 Gary , IN Standard 7,184 $44,667 $78,800
46410 Merrillville , IN Standard 39,243 $64,127 $208,100
46411 Merrillville , IN No street area — — —

Cite this page

zipcodes.pro. “Lake County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/in/county/lake

Underlying data is public domain or openly licensed — sources, vintages and licences.