Complete Guide to Illinois Phone Area Codes

Need to identify or obtain an Illinois-based phone number? This detailed guide covers all major and minor Illinois area codes

From local users to virtual phone system seekers, grasping the phone number structure in Illinois helps with routing calls, marketing, and compliance.

What Are Area Codes in Illinois?

The area code system in Illinois segments regions for organized call routing, helping manage number allocation across cities.

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 – Central Illinois including Springfield
• 309 – Peoria, Bloomington, and western parts of IL
• 312 – Central Chicago zone
• 773 – Northwest and South Side of Chicago
• 872 – Covers greater Chicago metro
• 847 – Northern suburbs including Evanston
• 224 – Also covers northern suburbs
• 630 – Western suburbs
• 331 – Overlay for 630
• 708 – Southwest Chicago suburbs
• 815 – Spans northern rural regions
• 779 – Overlay for 815
• 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 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

Using Illinois Phone Codes for Business Presence

Entrepreneurs and service providers rely on click here local numbers to establish trust, improve response rates, and localize presence.

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.

Overlay Area Codes in Illinois

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

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)

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

This flexibility helps businesses scale, reach target markets, and streamline support.

Get a Business Number with an Illinois Area Code

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.

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

Illinois Area Code: Common Questions Answered