Everything You Should Know About Illinois Area Codes

Need to identify or obtain an Illinois-based phone number? We’ll break it all down for you in this comprehensive post includes everything from historical area code changes to VoIP business solutions

Whether you're a resident, traveler, or business owner, understanding Illinois’ telephone code system is crucial for communication.

How Illinois Phone Codes Work

Area codes in Illinois are three-digit numbers assigned to different regions, helping manage number allocation across cities.

Supervised by NANPA and the FCC,, Illinois codes align with the NANP guidelines used across North America. For official standards, visit NANPA’s website.

Illinois Area Code List

Here is a breakdown showing city coverage and overlays:

• 217 – Central Illinois including Springfield
• 309 – Peoria, Bloomington, and western parts of IL
• 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 – Rockford and northern IL
• 779 – Overlay for 815
• 464 – Newest overlay for Chicago

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

Illinois Area Code Search Tools

There are many reliable lookup 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

Entrepreneurs and service providers rely on local numbers to appear local and trustworthy in customers’ eyes.

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

Looking to get started? Check out Bling’s virtual number options today.

Illinois Area Code Overlays

Many IL area codes now have overlays due to high population and business growth.

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

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

How VoIP Is Changing Illinois Phone Systems

VoIP more info 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.

Buying an Illinois Local Business Number

Local numbers are critical for customer trust.

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