DeKalb County, Illinois
13 ZIP codes · 631.34 sq mi of land · FIPS 17037
| Population | 100,703 |
|---|---|
| State | Illinois |
| FIPS code | 17037 |
| Time zone | Central |
| Land area | 631.34 sq mi |
| Center (lat, long) | 41.8946, -88.7690 |
Area codes in this area
These are the area codes that most often serve DeKalb County (including overlays). The exact area code depends on the phone number — landlines, mobiles and overlays can differ even on the same street.
Cities and towns (largest first)
Sycamore · 18,559ClareCortlandDekalbGenoaKingstonKirklandMaltaHinckleySandwichShabbonaSomonaukWaterman
ZIP codes in DeKalb County
60111 Clare60112 Cortland60115 Dekalb60135 Genoa60145 Kingston60146 Kirkland60150 Malta60178 Sycamore60520 Hinckley60548 Sandwich60550 Shabbona60552 Somonauk60556 Waterman
Population: U.S. Census Bureau, ACS 5-year estimates, 2024.