Serving the defendant
The plaintiff chooses the method. At the plaintiff's request the circuit clerk will serve the summons and complaint by certified or registered mail in lieu of personal service (Rule 284); otherwise the plaintiff arranges service by the county sheriff or a court-appointed special process server.
- County sheriff — personal service
- Court-appointed special process server — personal service
- Clerk-sent certified or registered mail, return receipt requested, restricted delivery to a natural person (Rule 284) — $2 per defendant plus the cost of mailing, paid to the clerk
Certified- or registered-mail service is not proved unless the return receipt shows delivery at least 21 days before the appearance date and restricted-delivery requirements are met; if it fails, the plaintiff must re-serve by sheriff or special process server.
Where filers get this wrong
Two things about service are consistently misunderstood:
- The clerk accepts your filing whether or not service is later done properly. The counter is not the check.
- Whether service was good gets tested afterwards — typically at the moment you ask the court for a default because the defendant did not appear.
Under Rule 284 the return receipt must show delivery at least 21 days before the day set for appearance to constitute proof of service. The clerk mails the summons and complaint and files the returned receipt.
Certified- or registered-mail service is not proved unless the return receipt shows delivery at least 21 days before the appearance date and restricted-delivery requirements are met; if it fails, the plaintiff must re-serve by sheriff or special process server.
The order it has to happen in
- 1. File first. The court issues the summons. Papers that have not been issued cannot be served.
- 2. Choose a permitted method. Illinois permits 3 routes, listed above. Which is wise depends on the defendant, not on which is cheapest.
- 3. Give a real, current address. A registered agent address for a business, a residence for a person. A stale address is the most common reason service fails and a case simply stops moving.
- 4. Get the proof on the docket. The server files a return of service. Without it the court treats the defendant as never notified.
Certified- or registered-mail service is not proved unless the return receipt shows delivery at least 21 days before the appearance date and restricted-delivery requirements are met; if it fails, the plaintiff must re-serve by sheriff or special process server.
- Claim limit
- $10,000
- Court
- Circuit Court
- File online
- Yes (statewide)
- Appeal window
- 30 days
Common questions
Who serves small claims papers in Illinois?
The plaintiff chooses the method. At the plaintiff's request the circuit clerk will serve the summons and complaint by certified or registered mail in lieu of personal service (Rule 284); otherwise the plaintiff arranges service by the county sheriff or a court-appointed special process server.
Can I serve the papers myself in Illinois?
No. Service is carried out by someone who is not a party to the case. Handing the papers over yourself does not count, and the defect usually surfaces at the worst moment.
Can small claims papers be served by mail in Illinois?
Illinois permits a mail route where the case type allows it. Certified- or registered-mail service is not proved unless the return receipt shows delivery at least 21 days before the appearance date and restricted-delivery requirements are met; if it fails, the plaintiff must re-serve by sheriff or special process server.
What happens if the defendant cannot be found?
The case does not move forward. Courts have alternative-service procedures for that situation, but they have to be applied for and they are not granted automatically.
Pick the county where you would sue
Small claims is filed at the county level. Pick your county for its court, fee, and forms — or start your claim and we'll ask where you'd sue.
Start my claimYour small claims filing packet — $49
Everything above, assembled and filled in with your facts:
- Your court's own forms, with your claim written in the language the court expects
- A demand letter built from the same facts
- A filing checklist with your court's address, hours, and fee
- What to bring to your hearing
Answer a few questions first. See your claim written out before you pay anything.
Reviewed by Small Claims Desk · Last reviewed 2026-08-20 · Sourced from Illinois judiciary self-help resources and each county's clerk of court and Ill. S. Ct. Rules 281-289 (Small Claims). See how we verify.