Procedures for State of Illinois Interagency Mail Service

  • Interagency mail should be addressed as legibly and accurately as U.S. mail. Give the recipient's first and last name and the complete department name and location. Always include a complete return address.
  • Separate outgoing mail into two stacks: interagency mail and U.S. Postal Service mail.
  • Interagency mail is only delivered to the Springfield and metro Chicago area offices listed in this service guide.
  • Interagency mail picked up in Springfield and Chicago destined for the same city will be delivered on the same or following day.
  • Interagency mail picked up in Springfield and Chicago destined for the other city will be delivered according to the schedule; Chicago and Springfield exchange mail on Mondays, Wednesdays and Fridays. Interagency mail destined for the other city may also be dropped off at a CMS mail center prior to 4:30 p.m. for next day delivery.
  • Contact the CMS Springfield or Chicago office to track interagency mail that has already been sent or to arrange for a large pickup.
  • Contact your agency mailroom authority if you wish to expand or change your interagency mail service.

Contact Information

Mail and Messenger Services
200 E. Ash St.
Springfield, IL 62704
Phone: (217) 782-2536 - Ext. 200 or 204

Mail and Messenger Services
James R. Thompson Center, C100
100 W. Randolph St.
Chicago, IL 60601-2613
Phone: (312) 814-2196