New Mexico Small Claims Court for Unpaid Invoices and Bills

When an Invoice Goes From Late to Legal

You sent the invoice. You followed up. Maybe you sent a formal demand letter with a 10–14 day deadline. The client or customer still hasn't paid. If the amount is $10,000 or less, New Mexico small claims court gives you a straightforward path to a judgment — without hiring an attorney.

Small claims works well for unpaid invoices because the facts are usually clean. You performed a service or delivered goods, you billed for it, the other side didn't pay. The dispute is about money owed, which is exactly what these courts are designed to resolve.

Statute of Limitations for Unpaid Debts

Your deadline to file depends on whether the agreement was in writing:

• Written contract or invoice with signed terms: 6 years from the date of breach (NMSA § 37-1-3)
• Oral agreement or handshake deal: 4 years from the date of breach (NMSA § 37-1-4)

The clock starts when the payment was due, not when you gave up on collecting. If you have a written contract that specified "net 30" and the invoice date was March 1, the breach date is March 31 — that's when the 6-year window begins.

Building Your Case Before You File

Strong unpaid invoice claims share a common evidence pattern:

1. The agreement — a signed contract, a written proposal the client accepted, an email chain confirming the scope and price, or a purchase order
2. Proof of delivery — completion photos, delivery receipts, signed acceptance forms, email confirmations that work was received
3. The invoice itself — with the date, amount, payment terms, and any past-due notices
4. The demand letter — your formal written demand, sent by certified mail with return receipt, giving the debtor 10–14 days to pay before you file suit
5. Communication records — emails, text messages, or voicemails showing the debtor acknowledged the debt or made excuses

A demand letter isn't legally required for most invoice claims (unlike security deposit disputes, which have specific notice requirements). But judges expect to see that you tried to resolve the matter before filing, and a certified-mail demand letter with a signed return receipt proves the debtor knew the claim was coming.

Filing the Complaint

File Form 4-201 (Magistrate Court, outside Bernalillo County) or Form 4-202 (Metropolitan Court, Bernalillo County) with the court clerk. The filing fee is $77. In the complaint, state the amount owed, the basis for the debt (the contract or agreement), and, if you made a demand, briefly describe it and any response.

Name the defendant correctly. If you're suing a business, search the New Mexico Secretary of State's online portal for the registered entity name. An LLC must be sued as "Acme Services, LLC" — the exact name on file. A sole proprietor gets sued individually: "Jane Doe, individually and d/b/a Acme Home Services."

At the Hearing

Bring the original contract (or the best evidence of your agreement), the invoice, your demand letter with the certified mail receipt, and any emails or texts showing the debtor acknowledged the debt. Bring the original plus at least three clean copies of each exhibit — one set for the judge, one for the defendant, one for witnesses, and one for yourself.

The judge will ask you to explain what happened. Keep it factual: what the agreement was, what you delivered, when payment was due, that the defendant didn't pay, and what you did to try to collect. If the defendant doesn't show up, you can request a default judgment.

If the defendant claims the work was defective or incomplete, you'll need to counter with delivery proof and completion records. Repair estimates from independent contractors help if the dispute is about quality.

After the Judgment

A judgment in your favor doesn't automatically put money in your account. If the debtor still won't pay, you may need post-judgment enforcement — wage garnishment, bank account garnishment, or a property lien. That process is covered in New Mexico's post-judgment collection procedures.

The New Mexico small claims filing guide walks through each step from demand letter to hearing preparation, with worksheets for calculating your damages and tracking every deadline along the way.

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