Chicago Linux
- A GNU/Linux Users Group in downtown Chicago. Join the mailing lists, IRC, or come to a meeting.
- http://www.chicagolug.org/

Rock River Linux Users Group ( RRLug)
- A Linux Users Group based in Rockford, Illinois. The site contains events and presentations, a library, book reviews, and screenshots.
- http://linux.rockriver.net/

Chicagoland Linux Users Group
- Gathering in the Chicago area. Includes meeting times, install fest information and a mailing list.
- http://www.luni.org/

NWCLUG
- Northwest Chicagoland Linux User Group.
- http://nwclug.harper.cc.il.us/httpd/html/index.html

Southern Illinois Linux Users Group
- Linux users group of Carbondale (Southern Illinois University) and the surrounding area.
- http://www.silug.org/

Linux Users of Central Illinois
- The Linux Users Group of Springfield, Illinois and the surrounding area.
- http://www.luci.org/

SLUUG- St. Louis Unix Users Group
- Vendor-independent organization dedicated to promoting Open Systems and the Linux and UNIX operating systems.
- http://www.sluug.org/