Illinois Area Codes Explained

Are you wondering what area code corresponds to your Illinois city? read more We’ll break it all down for you in this comprehensive post covers all major and minor Illinois area codes

No matter if you’re launching a business or tracing a call, grasping the phone number structure in Illinois is essential for seamless contact and verification.

What Are Area Codes in Illinois?

Area codes in Illinois are three-digit numbers assigned to different regions, allowing calls to be directed accurately.

Structured by the NANP, Illinois codes align with the NANP guidelines used across North America. 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 – Western central Illinois
• 312 – Downtown Chicago only
• 773 – Northwest and South Side of Chicago
• 872 – Covers greater Chicago metro
• 847 – Northern suburbs including Evanston
• 224 – Also covers northern suburbs
• 630 – Covers DuPage County, Naperville, Wheaton
• 331 – Overlay for 630
• 708 – Oak Lawn, Cicero
• 815 – Spans northern rural regions
• 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.

Illinois Area Code Search Tools

There are many reliable lookup tools 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

Why Businesses Choose Local Illinois Numbers

Entrepreneurs and service providers rely on local numbers to boost call pick-up rates and brand visibility.

Modern business platforms make it simple to buy or assign IL-based numbers.

If you're setting up a professional phone system with a local presence, explore business phone systems from Bling.

New and Duplicate Area Codes in IL

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)

Each overlay covers the same geographic region as the original area code.

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

Illinois Area Codes & VoIP Technology

With the rise of cloud calling, VoIP is becoming 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.

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

Illinois Area Code: Common Questions Answered