Service of process in Illinois
In Illinois, process is served by the sheriff (or a coroner if the sheriff is disqualified), or, without special appointment, by a person licensed or registered as a private detective; the court may also appoint a non-party adult over 18 to serve (735 ILCS 5/2-202). There is no fixed number of days to serve, but Illinois Supreme Court Rule 103(b) requires reasonable diligence and allows dismissal for delay.
ProcessServerState provides procedural-information-only summaries of state process-server rules. This is not legal advice. Service of process is a critical step in litigation — if you fail to serve correctly, your case can be dismissed. For complex or contested matters, consult a licensed attorney or a court self-help center. Not affiliated with any court or sheriff's office.
Is a license required in Illinois?
Authority: Illinois Department of Financial and Professional Regulation (IDFPR), under the Private Detective Act of 2004
A licensed private detective (or registered employee of a certified agency) may serve process in any county without court appointment. A non-licensed private person 18+ and not a party may serve only if the court so orders by motion.
Who may serve process in Illinois?
- County sheriff
- Licensed / registered process server
- Any non-party adult (18+)
- Certified / registered mail
- Publication (by court order)
Service deadline (Illinois)
No fixed day-count deadline. Ill. Sup. Ct. R. 103(b) requires 'reasonable diligence' in obtaining service; failure may lead to dismissal (totality-of-circumstances standard).
UIDDA: Illinois has adopted the Uniform Interstate Depositions and Discovery Act for interstate service.
Sheriff / Marshal civil-process route
Civil-process fees are set by each county and listed on the local sheriff's civil-process page. Not all counties publish a fee schedule — confirm with the county where service will be made.
Statute / Rule citation
735 ILCS 5/2-202 (with Ill. Sup. Ct. R. 102 on manner of service)
UIDDA: 735 ILCS 35/1 et seq. (eff. Jan. 1, 2016, P.A. 99-79)
Verification notes for Illinois: the following could not be fully primary-source-confirmed in our last pass and should be verified against the cited source before you rely on them:
- rule4Url (ILGA index page; statute text verified via FindLaw mirror)
Interstate service from Illinois
Illinois has adopted the Uniform Interstate Depositions and Discovery Act (UIDDA), which provides a streamlined process for issuing an out-of-state subpoena based on one issued in the trial state. Service of an initial summons across state lines follows the receiving state's rules.
Sources for Illinois
Other states with licensing requirements
Check a different state
Verified against Illinois primary sources on June 16, 2026. Read how we verify on our methodology page, or browse every citation in the source manifest.
Editorial review status: Reviewer attribution pending — we are recruiting a credentialed reviewer (ex-process-server with a NAPPS credential, or a NALA/NFPA-certified civil-procedure paralegal) before this site applies for advertising. We will not display a fabricated reviewer.
ProcessServerState provides procedural-information-only summaries of state process-server rules. This is not legal advice. Service of process is a critical step in litigation — if you fail to serve correctly, your case can be dismissed. For complex or contested matters, consult a licensed attorney or a court self-help center. Not affiliated with any court or sheriff's office.