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Unpaid invoice in Illinois small claims

Client won't pay your invoice? Collect it in small claims.

If a client or customer has not paid an invoice for work you delivered or goods you sold, small claims court is a low-cost way to collect. You do not need a lawyer. The strength of your case usually comes down to clear proof: the agreement or terms, the invoice, evidence the work or goods were delivered, and a record of your attempts to collect.

In Illinois, small-claims cases are heard in the Circuit Court (Small Claims) and you can sue for up to $10,000.

Unpaid invoice: steps that matter

  1. Send a final written demand (a clear statement of what is owed and a payment deadline) and keep proof you sent it.
  2. Gather your contract or written terms, the invoice, delivery/completion proof, and any messages showing the other side accepted the work.
  3. Confirm you are within the statute of limitations below before you file.
  4. File in the correct court for where the defendant is or where the work happened, and keep every date and document together.

Filing your Small Claims Complaint (filed together with a Small Claims Summons) in Illinois

  1. Fill out the Small Claims Complaint and Small Claims Summons. Name yourself as Plaintiff and the person or business as Defendant (use the correct legal name and address). In paragraph 5 of the Complaint, state the facts and the amount owed (must be $10,000 or less); if the claim is based on a written document such as a lease or contract, attach a readable copy. Complete a separate Summons for each Defendant and ask the Circuit Clerk for the court date to enter in Section 4.
  2. File the forms with the Circuit Clerk (e-file). File the Small Claims Complaint and Small Claims Summons with the Circuit Clerk. You must electronically file (e-file) unless you qualify for an exemption (e.g., an inmate without a lawyer, a disability, no internet/computer access, or difficulty reading/speaking English, using a Certification for Exemption from E-Filing). To e-file, create an account with an e-filing service provider via illinoiscourts.gov/service-providers.htm; the Circuit Clerk's office offers public terminals if you need help.
  3. Serve the Defendant. Serve each Defendant by one of three ways: through the Circuit Clerk by certified mail (least expensive; only the Clerk may mail it), through the county sheriff (hand delivery, more expensive), or through a special process server. Pay the applicable fees for each party or provide an Order for Waiver of Court Fees.
  4. Confirm service and get/confirm the court date. The person who serves the papers completes the Proof of Service section of the Summons and files it with the Circuit Clerk or mails it to you. Ask the Circuit Clerk whether a court date is scheduled automatically or whether you must schedule it, and whether the court or you must send the Notice of Court Date to the other party.
  5. Appear and present your case. Go to court on the appearance date, bring copies of everything you filed, any witnesses, documents/photos, and a photo ID, and present your case to the judge, who issues a written judgment (Small Claims Order).

Filing fees: Filing and service fees are set locally and vary; confirm the current amount with the court. A fee waiver is available if you cannot afford the costs.

Deadline that applies to your unpaid invoice

An unpaid invoice is usually a contract or account claim. If you had a signed agreement or written terms, the written-contract statute of limitations below typically applies; a purely verbal deal usually falls under the oral-contract period. That statute is the deadline to file, so do not wait too long.

Written contract: 10 years (735 ILCS 5/13-206)

Answering a lawsuit: The summons sets an appearance date not less than 40 nor more than 61 days after issuance; the defendant generally need not file a written answer unless ordered by the court.

Serving the defendant: Serve each Defendant by one of three methods: (1) through the Circuit Clerk by certified/registered mail (least expensive; only the Clerk may mail it), (2) through the county sheriff by hand delivery, or (3) through a special process server. The server completes the Proof of Service on the Summons. Under Supreme Court Rule 284, mail service requires return receipt and is proof of service if delivery is shown at least 21 days before the appearance day.

Appeals: If you lose, you have 30 days to file a Motion asking the judge to reconsider the ruling or to file an appeal to a higher court (using the appellate forms).

This page is general information, not legal advice, and CaseBySelf is not a law firm. Rules, fees, and deadlines change and vary by court: verify with the specific court where you file. Source: Office of the Illinois Courts - Small Claims (self-help). Last reviewed 2026-06-23.