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/DEKALB

DeKalb County, IL ZIP codes

There are 13 ZIP codes in DeKalb County, IL, in 13 towns, from 60111 to 60556. The largest are 60115 (Dekalb), 60178 (Sycamore) and 60548 (Sandwich). 1 more crosses into it from a neighbouring county: 60518.

The county seat is Sycamore.

ZIP codes
13
Partly in it
1 more
Towns
13
County seat
Sycamore
County FIPS
17037
Population
100,703
Median household income
$70,724
Land area
631 sq mi
Area codes
779, 815

DeKalb County ZIP codes by town

Sycamore (county seat)
60178

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 DeKalb County

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

Map of DeKalb County ZIP codes

60111601126011560135601456014660150601786052060548605506055260556

The ZIP codes of DeKalb 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.

DeKalb County in numbers

About 100,703 people live in DeKalb County, in 39,550 households, the 20th most populous of Illinois's 102 counties. The median household income is $70,724 a year, 15% below the Illinois median of $83,390 (US: $80,734). The median owner-occupied home is valued at $243,600 (7% below the Illinois median), and median gross rent is $1,049 a month. The median age is 32.7; 33.0% of adults 25 and over hold a bachelor's degree or higher (37.8% across Illinois); the average commute takes 27 minutes.

Population100,703DeKalb100,703
Households39,550DeKalb39,550
Median age32.7DeKalb32.7Illinois39.0US 38.9
Median household income$70,724DeKalb$70,724Illinois$83,390US $80,734
Median home value$243,600DeKalb$243,600Illinois$263,300US $332,700
Median gross rent$1,049DeKalb$1,049Illinois$1,274US $1,413
Bachelor's degree or higher33.0%DeKalb33.0%Illinois37.8%US 35.7%
Mean commute26.7 minDeKalb26.7 minIllinois27.8 minUS 26.4 min
Population density160 / sq miDeKalb160 / 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 DeKalb County

Largest towns in DeKalb County
TownZIP codesPopulation
Dekalb 1 40,443
Sycamore 1 18,559
Sandwich 1 7,219
Genoa 1 5,492
Cortland 1 4,564
Hinckley 1 2,331
Somonauk 1 1,569
Kirkland 1 1,525
Waterman 1 1,448
Kingston 1 1,352
Malta 1 1,274
Shabbona 1 572
Clare 1 257

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 DeKalb County.

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

Every ZIP code in DeKalb County, with figures

ZIP codes in DeKalb County
ZIP City Type Population Median income Median home
60111 Clare , IL Standard 257 $84,583 $375,900
60112 Cortland , IL Standard 4,621 $72,831 $229,900
60115 Dekalb , IL Standard 42,536 $47,043 $208,600
60135 Genoa , IL Standard 7,274 $98,033 $254,000
60145 Kingston , IL Standard 2,464 $108,477 $268,300
60146 Kirkland , IL Standard 2,369 $88,032 $222,000
60150 Malta , IL Standard 1,738 $86,719 $188,400
60178 Sycamore , IL Standard 22,224 $92,913 $279,500
60520 Hinckley , IL Standard 2,979 $98,958 $320,500
60548 Sandwich , IL Standard 11,721 $82,957 $262,100
60550 Shabbona , IL Standard 941 $81,574 $223,000
60552 Somonauk , IL Standard 4,285 $113,411 $257,400
60556 Waterman , IL Standard 2,138 $100,186 $234,800

Cite this page

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

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