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/IL/COUNTY/MONROE

Monroe County, IL ZIP codes

There are 8 ZIP codes in Monroe County, IL, in 8 towns, from 62236 to 62298. The largest are 62298 (Waterloo), 62236 (Columbia) and 62278 (Red Bud). 1 more crosses into it from a neighbouring county: 62277.

The county seat is Waterloo.

ZIP codes
8
Partly in it
1 more
Towns
8
County seat
Waterloo
County FIPS
17133
Population
35,036
Median household income
$102,880
Land area
385 sq mi
Area codes
618, 730
Metro area
St. Louis

Monroe County ZIP codes by town

Waterloo (county seat)
62298

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 Monroe County

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

Map of Monroe County ZIP codes

6223662244622486225662278622796229562298

The ZIP codes of Monroe 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.

Monroe County in numbers

About 35,036 people live in Monroe County, in 13,851 households, the 40th most populous of Illinois's 102 counties. The median household income is $102,880 a year, 23% above the Illinois median of $83,390 (US: $80,734). The median owner-occupied home is valued at $282,100 (7% above the Illinois median), and median gross rent is $1,042 a month. The median age is 43.2; 38.7% of adults 25 and over hold a bachelor's degree or higher (37.8% across Illinois); the average commute takes 28 minutes.

Population35,036Monroe35,036
Households13,851Monroe13,851
Median age43.2Monroe43.2Illinois39.0US 38.9
Median household income$102,880Monroe$102,880Illinois$83,390US $80,734
Median home value$282,100Monroe$282,100Illinois$263,300US $332,700
Median gross rent$1,042Monroe$1,042Illinois$1,274US $1,413
Bachelor's degree or higher38.7%Monroe38.7%Illinois37.8%US 35.7%
Mean commute28.3 minMonroe28.3 minIllinois27.8 minUS 26.4 min
Population density91 / sq miMonroe91 / 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 Monroe County

Largest towns in Monroe County
TownZIP codesPopulation
Waterloo 1 11,129
Columbia 1 11,127
Red Bud 1 3,782
Valmeyer 1 1,090
Fults 1 928
Hecker 1 521
Renault 1 112
Maeystown 1 65

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 Monroe County.

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

Every ZIP code in Monroe County, with figures

ZIP codes in Monroe County
ZIP City Type Population Median income Median home
62236 Columbia , IL Standard 14,154 $108,981 $306,600
62244 Fults , IL Standard 928 $107,917 $252,400
62248 Hecker , IL Standard 521 $79,583 $166,800
62256 Maeystown , IL Standard 35 $126,250 $158,300
62278 Red Bud , IL Standard 6,281 $79,688 $178,300
62279 Renault , IL Standard 112 $139,063 —
62295 Valmeyer , IL Standard 1,459 $87,989 $203,400
62298 Waterloo , IL Standard 18,208 $101,155 $290,200

Cite this page

zipcodes.pro. “Monroe County ZIP codes.” Data release 2026-10-12. Retrieved 2026-10-20. https://zipcodes.pro/state/il/county/monroe

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