Everything You Should Know About Illinois Area Codes

Need to identify or obtain an Illinois-based phone number? You’ve come to the right place—this blog dives into lookup tools, city-based breakdowns, and more.

No matter if you’re launching a business or tracing a call, knowing the dialing system across IL helps with routing calls, marketing, and compliance.

How Illinois Phone Codes Work

Illinois telephone area codes identify specific geographic territories, allowing calls to be directed accurately.

Structured by the NANP, the state of Illinois adheres to NANP’s numbering scheme. For official standards, visit NANPA’s website.

Active Area Codes in IL

Find all the active codes below showing city coverage and overlays:

• 217 – Covers Springfield, Champaign, and surrounding areas
• 309 – Peoria, Bloomington, and western parts of IL
• 312 – Downtown Chicago only
• 773 – Rest of Chicago outside downtown
• 872 – Covers greater Chicago metro
• 847 – Northern suburbs including Evanston
• 224 – Overlay for 847
• 630 – Covers DuPage County, Naperville, Wheaton
• 331 – Used in the same region
• 708 – Southwest Chicago suburbs
• 815 – Rockford and northern IL
• 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

Several trusted databases to find an Illinois area code by city or number.

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

Companies looking to reach customers in Illinois often opt for local numbers to establish trust, improve response rates, and localize presence.

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 cloud phone platforms from Bling.

Overlay Area Codes in Illinois

To prevent exhaustion of available numbers, Illinois has implemented overlays in many regions.

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)

Overlay central Illinois area codes codes don’t replace old ones but coexist in the same region.

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

Phone area codes in Illinois follow regional distributions across the state.

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

Illinois Area Codes & VoIP Technology

Voice over IP (VoIP) services have revolutionized how people and businesses use area codes.

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

How to Get a Local Number in Illinois

Getting a business phone number with an Illinois area code enhances regional credibility.

You can register a business phone number with any Illinois code through platforms like Bling.

It’s also scalable for multiple team members and departments.

FAQ – Illinois Phone Codes