| Code | | Site | | Code | | Site | | Code | | Site |
| MA5 | | Arlington Hights Sectional | |
MAC | | Ace of Clubs | |
MAJ | | The Ace of Clubs Jeremiah/Tues | |
| MAL | | Admiral at the Lake Bridge Clu | |
MBT | | All Bridge Saints | |
MC4 | | Chicago Sectional | |
| MC5 | | Crystal Lake Sectional | |
MCL | | CBG Thursday | |
MCO | | ??? | |
| MCT | | Chicago Cultural Center Monday | |
MCY | | Country Club Bridge League | |
MD5 | | Darien Sectional | |
| ME4 | | Elmhurst Sectional | |
MEW | | New Eazy Bridge/Wednesday | |
MG6 | | Glenview Sectional | |
| MH5 | | Highland Park Sectional | |
MJT | | Tom's Game | |
ML5 | | Lombard Sectional | |
| MLJ | | New Lenox-Joliet DBC | |
MLS | | Lawson Bridge Studio | |
MLT | | ??? | |
| MNE | | New Easy Bridge | |
MNF | | ??? | |
MNS | | Northshore DBC | |
| MNW | | Northwestern DBC | |
MOY | | Olympia DBC | |
MP4 | | Palantine Sectional | |
| MQN | | Queen of Clubs | |
MR6 | | Rolling Meadows Sectional | |
MS4 | | Skokie Sectional | |
| MTT | | Tree Towns DBC | |
MUD | | Reluctant Redoubler DBC | |
MW5 | | Wheeling Sectional | |
| MWS | | West Suburban DBC | |
MWV | | Wheaton Thursday DBC | |
MYV | | Yorkville DBC | |