3-105.Service of summons.
Article III. Administrative Review · Last amended 2008 · Last verified July 20, 2026
Full Text of 735 ILCS 5/3-105
Plain-English Summary
Section 3-105 requires that a summons issued in a review action be served by registered or certified mail on the administrative agency and on each other defendant. An exception applies to review of a decision of a regional board of school trustees, regional superintendent of schools, or the State Superintendent of Education, when a committee of 10 has been designated under Section 7-6 of the School Code — in that case, only the agency and each member of the committee of 10 need be served.
Where the act governing the agency's procedure specifies a method of service, that method controls; otherwise, the decision (and, by the same default, the summons) is deemed served when personally delivered, or when deposited in the mail, in a sealed, postage-prepaid envelope, addressed to the affected party's last known residence or place of business.
The section builds in two related safe harbors. No action is dismissed for lack of jurisdiction based on a failure to serve an individual employee, agent, or member of an agency, board, committee, or government entity who acted in an official capacity, as long as the agency, board, committee, or entity itself was served. Service on the director or agency head, in that person's official capacity, counts as service on the entity — and the reverse holds too: no action is dismissed for failing to serve the entity where the director or agency head, in an official capacity, was served instead.
On the mechanics, the clerk of the court serves the agency by mailing a copy of the summons to its main office in the State, and mails a copy to each other defendant at the last known address the plaintiff supplies by affidavit filed with the complaint. The clerk's certificate that service was made under this section is evidence that it was done.
Frequently Asked Questions
How is the summons served on an administrative agency in a review action?
By registered or certified mail, sent by the clerk of the court to the agency at its main office in the State.
What happens with service when a school committee of 10 is involved?
Only the administrative agency and each member of the committee of 10 designated under Section 7-6 of the School Code need to be served, in place of the ordinary rule requiring service on each defendant.
Can my case be dismissed if I served the agency head but not the agency by name?
No. Service on the director or agency head, in an official capacity, is deemed service on the administrative agency, board, committee, or government entity, so a failure to separately name and serve the entity doesn't cause a dismissal for lack of jurisdiction.
Who is responsible for mailing the summons to the defendants?
The clerk of the court mails a copy of the summons to the agency at its main office and mails a copy to each other defendant at the address the plaintiff has designated.
How does a plaintiff make sure the clerk has the right addresses for service?
By affidavit filed with the complaint, the plaintiff designates the last known address of each defendant to be served, and the clerk's certificate that service was made under this section serves as evidence that it was done.
Amendment History
(Source: P.A. 95-831, eff. 8-14-08.)