Illinois ZIP Codes: Ranges, Prefixes and Major Cities

Illinois uses 1,568 active ZIP codes, running from 60002 to 62999. This guide shows how those codes are grouped, which ones serve the state's largest cities and how to format them correctly.

ZIP code range and prefixes

Every Illinois ZIP code starts with one of 29 three-digit prefixes. Each prefix points to a sectional center facility, the processing plant that sorts mail for a group of nearby post offices.

  • 600
  • 601
  • 602
  • 603
  • 604
  • 605
  • 606
  • 607
  • 608
  • 609
  • 610
  • 611
  • 612
  • 613
  • 614
  • 615
  • 616
  • 617
  • 618
  • 619
  • 620
  • 622
  • 623
  • 624
  • 625
  • 626
  • 627
  • 628
  • 629

Types of ZIP codes in Illinois

TypeCountWhat it covers
Standard1,258Street delivery areas
PO Box228Post office boxes only
Unique82A single high-volume organization

ZIP codes for major Illinois cities

CityCountyStandard ZIPsRange
ChicagoCook County5860601–60701
RockfordWinnebago County961101–61114
PeoriaPeoria County861602–61615
SpringfieldSangamon County762701–62712
East Saint LouisSt. Clair County662201–62207
AuroraDuPage County560502–60506
JolietWill County560431–60436
BellevilleSt. Clair County462220–62226
DecaturMacon County462521–62526
NapervilleDuPage County460540–60565
SchaumburgCook County460173–60195
BloomingtonMcLean County361701–61705
CarbondaleJackson County362901–62903
ChampaignChampaign County361820–61822
ElginKane County360120–60124

Springfield is the state capital. Larger cities have many ZIP codes because each code follows mail delivery routes, not city limits.

Sample addresses

James Reed 919 Main Rd Bloomington, IL 61705
David Chen 9233 Pine Blvd Aurora, IL 60505
Mary Smith 6847 Summit Pl Belleville, IL 62223

These examples use real city and ZIP pairs with invented street lines, so they are safe for testing and documentation.

Tips for working with these ZIP codes

  • Store ZIP codes as text, not numbers, so the format stays consistent across states with leading zeros.
  • All of Illinois is in the Central time zone, which keeps scheduling logic simple.
  • A quick sanity check: a valid IL ZIP code begins with one of the prefixes listed above.
  • City names in addresses are post office names. A suburb may share a ZIP code and city name with a nearby larger town.

Create realistic Illinois addresses for testing, with real cities, counties and ZIP codes.

Generate Illinois addresses