Everything You Should Know About Illinois Area Codes

Trying to understand which area code to use for your business in Illinois? You’ve come to the right place—this blog covers all major and minor Illinois area codes

From local users to virtual phone system seekers, understanding Illinois’ telephone code system is crucial for communication.

What Are Area Codes in Illinois?

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

Supervised by NANPA and the FCC,, Illinois area codes follow a format shared across the U.S. and Canada. For official standards, visit NANPA’s website.

Illinois Area Code List

Below is a current list of Illinois area codes organized by coverage area:

• 217 – Covers Springfield, Champaign, and surrounding areas
• 309 – Peoria, Bloomington, and western parts of IL
• 312 – Central Chicago zone
• 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 – Overlay for 630
• 708 – Oak Lawn, Cicero
• 815 – Rockford and northern IL
• 779 – Same coverage region
• 464 – Launched to support number exhaustion

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

How to Lookup Illinois Area Codes

Several trusted databases to discover which city an area code belongs to.

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 boost call pick-up rates and brand visibility.

With services like Bling Cloud, businesses can instantly activate virtual numbers for any Illinois region.

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.

Here are the main overlays:

• 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 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

How VoIP Is Changing Illinois Phone Systems

With the rise of cloud calling, VoIP is becoming central Illinois area codes the preferred method for phone communication in Illinois.

Want to learn more? Visit Illinois VoIP phone solutions for powerful options.

Buying an Illinois Local Business Number

It also helps with branding, geo-targeting, and customer service.

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

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

FAQ – Illinois Phone Codes