Sue for Unpaid Invoice in Colorado Small Claims Court

Does Your Unpaid Invoice Qualify for Small Claims?

Colorado small claims court handles money claims up to $7,500 under C.R.S. § 13-6-403. If a client owes you within that range for delivered goods or completed services, you can file without hiring a lawyer.

The statute of limitations for written contracts in Colorado is 3 years from the date of breach under C.R.S. § 13-80-101(1)(a). Oral agreements have the same 3-year window. If the invoice went unpaid more than 3 years ago, the court will likely dismiss your claim.

Two practical thresholds to keep in mind: if the unpaid amount is under $500, the filing fee is $31. For amounts between $500.01 and $7,500, it is $55. If the client owes you more than $7,500, you can still file in small claims — but you waive recovery of anything above the cap.

Building Your Case: Documentation

The strength of an unpaid invoice claim comes down to paperwork. Gather these before filing:

• The contract or agreement — written contracts are strongest, but email chains confirming the scope, deliverables, and price work too. Even text messages where the client agreed to your quote establish the terms.
• Proof of delivery — completion photos, delivery receipts, signed acceptance, email confirmations that the work was done or goods received.
• The invoice itself — with the date sent, amount due, payment terms, and any follow-up invoices or statements.
• Payment history — partial payments, bounced checks, or Venmo/Zelle transaction records showing what was and was not paid.
• Written collection attempts — emails, texts, or letters asking for payment. These show the court you made reasonable efforts before filing.

Send a Demand Letter First

A formal demand letter is not legally required for most unpaid invoice claims, but it serves two purposes. First, it often gets you paid without going to court — many clients settle once they see a dated letter referencing small claims court. Second, it demonstrates to the judge that you gave the debtor a fair chance to pay.

Your demand letter should state the exact amount owed, reference the original agreement, set a deadline for payment (10 to 14 days is one practical choice, not a Colorado legal requirement), and state that you intend to file in small claims court if the balance is not resolved. Send it via certified mail so you have a signed return receipt as proof.

Identifying and Serving the Right Party

This is where unpaid invoice claims often go wrong. You must sue the correct legal entity:

• Individual clients — use their full legal name.
• Sole proprietors — name the individual owner plus the trade name (e.g., "Jane Smith d/b/a Smith Design Studio").
• LLCs and corporations — use the exact entity name registered with the Colorado Secretary of State at coloradosos.gov. Service may be made on an officer, manager, or designated registered agent under C.R.C.P. Rule 304; serving an unauthorized person can invalidate service.

After filing Form JDF 250, you have until at least 15 days before trial to complete service. For business entities, serve the registered agent at the address listed in the Secretary of State database.

At the Hearing

Bring three complete physical sets of your exhibits and label them with numbers (Exhibit 1, Exhibit 2, etc.) under C.R.C.P. Rule 512. Follow any court instructions about who should receive each set.

Your presentation follows a simple structure: show the agreement, show that you performed, show the invoice, show that it went unpaid, and show your demand and collection efforts. Digital evidence — emails, text messages, app screenshots — must be printed or on a flash drive. Courts do not accept evidence displayed on phone screens.

If the defendant does not appear after valid service at least 15 days before trial, the court may enter a default judgment in your favor under C.R.C.P. Rule 515, but you still need to present evidence supporting the amount claimed.

Interest on Unpaid Invoices

If your contract specifies an interest rate, the court applies that rate up to Colorado's 45% annual cap under C.R.S. § 5-12-103. If the contract is silent on interest, the statutory default rate is 8% per year under C.R.S. § 5-12-102, compounded annually from the date payment was due.

Include your interest calculation in the claim amount on Form JDF 250, and keep the principal at or under $7,500. The small claims limit is exclusive of prejudgment interest and allowable court costs.

Our Colorado Small Claims Filing Guide includes an entity verification worksheet, a filing cost estimator, and the deadline calendar — everything you need to move from unpaid invoice to filed claim without missing a step.

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