Complete Guide to Illinois Phone Area Codes

Trying to understand which area code to use for your business in Illinois? You’ve come to the right place—this blog dives into lookup tools, city-based breakdowns, and more.

From local users to virtual phone system seekers, knowing the dialing system across IL is crucial for communication.

Understanding Illinois Area Codes

The area code system in Illinois segments regions for organized call routing, supporting phone number management for personal and business use.

Administered by the North American Numbering Plan Administration (NANPA),, the state of Illinois adheres to NANP’s numbering scheme. For official standards, visit NANPA’s website.

Active Area Codes in IL

Below is a current list showing city coverage and overlays:

• 217 – Central Illinois including Springfield
• 309 – Western central Illinois
• 312 – Central Chicago zone
• 773 – Rest of Chicago outside downtown
• 872 – Overlay for 312 and 773
• 847 – Northern suburbs including Evanston
• 224 – Also covers northern suburbs
• 630 – Covers DuPage County, Naperville, Wheaton
• 331 – Used in the same region
• 708 – Southwest Chicago suburbs
• 815 – Spans northern rural regions
• 779 – Same coverage region
• 464 – Newest overlay for Chicago

To learn more about official overlays and numbering plans, visit the FCC Area Code Resources.

Find Area Codes for Illinois Cities

You can use online tools that help you identify the area code for a city or trace a phone call.

1. TrueCaller – Reverse lookup and spam detection
2. Whitepages – Detailed contact search and verification
3. Nomorobo – Great for spam and robocall filtering
4. YouTube: Illinois Area Codes Explained – Helpful visual resource
5. Wikipedia List – See historical and current Illinois codes

Illinois Virtual Numbers for Businesses

Businesses operating in or targeting Illinois use local area codes to boost call pick-up rates and brand visibility.

Using VoIP and virtual phone systems, getting a number with an Illinois area code is now easy and affordable.

If you're setting up a professional phone system with a local presence, explore Illinois-based VoIP services from Bling.

New and Duplicate Area Codes in IL

Illinois uses overlay area codes to handle the increasing demand for phone numbers.

These are the current overlays used in Illinois:

• 872 – Overlays 312 and 773 (Chicago)
• 464 – Newest overlay for 708 (Chicago suburbs)
• 224 – Overlays 847 (Northern suburbs)
• 331 – Overlays 630 (Western suburbs)
• 779 – Overlays 815 (Northern Illinois)

Users must now dial 10 digits, even for local calls, due to overlays.

Regional Breakdown: Northern, Central, and Southern Illinois Area Codes

Illinois is divided into three primary telephone regions: North, Central, and South.

Northern Illinois

• 312, 773, 872 – Chicago metro|Downtown and metro Chicago
• 847, 224 – Evanston, Waukegan, North Shore|Northern suburbs
• 630, 331 – Naperville, Wheaton, Oak Brook|Western suburbs
• 708, 464 – Cicero, Oak Lawn, South suburbs
• 815, 779 – Rockford, Joliet, Kankakee

Central Illinois

• 217 – Springfield, Urbana, Decatur
• 309 – Peoria, Bloomington, Galesburg

Southern Illinois

• 618 – East St. Louis, Carbondale, Belleville

Impact of VoIP on Illinois Numbers

VoIP lets you use any area code in Illinois without a physical presence.

Whether you're in downtown Chicago or remote southern Illinois, you can now get a local area code with VoIP solutions.

Get a Business Number with an Illinois Area Code

Local numbers are critical for customer trust.

For example, Illinois phone number for business instantly connects you with your target region.

You don’t need to be in Illinois physically—virtual systems handle routing Illinois dialing codes through VoIP or PBX networks.

Illinois Area Code: Common Questions Answered