618 area code — Collinsville, IL geographic

Data: NANPA public reports, current as of July 28, 2026.

State
Illinois
Major area
Collinsville
Time zone
Central
In service since
1947-01-01
Overlay complex
618 / 730
Active prefixes
786
Rate centers
242
Carriers
56
Projected exhaust
4Q 2040

Area code 618 is a geographic code serving Collinsville, Illinois in the Central time zone. It has been in service since January 1, 1947. Together with 730 it forms the 618/730 overlay. Because of number portability and VoIP, the area code tells you where the number was issued, not where the caller is right now.

NANPA lists 786 active NXX prefixes in 618, assigned to 56 carriers. 608 of those prefixes are pooled — shared between carriers in thousands-number blocks. The code spans 242 rate centers (billing localities).

Later relief produced 730 (2023) from its territory.

Official projections put exhaust for the 618/730 complex at 4Q 2040.

The dialing plan is 10D for home-NPA local calls and 10D across codes.

Use this page to decode where 618 numbers come from — and remember that spoofing means the screen can lie about everything except your own caution.

Largest localities in 618

Largest rate centers in area code 618
Locality (rate center)Active prefixesAlso served by
Collinsville 88 730
Carbondale 33 730
Belleville 31 730
Centralia 24 730
Granite City 22
Olney 16 730
Alton 15 730
Marion 15 730
Mount Vernon 14 730
East Saint Louis 14 730

FAQ

Will 618 run out of numbers?

NANPA's current forecast projects exhaust in 4Q 2040 — decades of capacity remain.

Why am I getting spam calls from 618 numbers?

Scammers spoof recognizable area codes so calls look local or familiar. A displayed 618 number does not prove the call originated there — see our guide to spotting spoofed calls.

Where is a 618 number from?

618 is assigned to Collinsville and surrounding areas of Illinois in the Central time zone. The three digits after the area code (the prefix) narrow it down to a rate center.

Is 618 a toll-free number?

No. 618 is a geographic code; calls are billed like any other domestic call. Toll-free codes are 800, 833, 844, 855, 866, 877 and 888.

Why do 730 and 618 cover the same place?

They are overlays: when a code runs low on numbers, a new code is added over the same territory instead of splitting it. The 618/730 complex shares one service area, and local calls are dialed with 10 digits.