Suing for an Unpaid Invoice or Money Owed in South Dakota Small Claims Court

Someone owes you money and won't pay. Maybe it's a client who ghosted after you finished the work, a friend who borrowed $2,000 and stopped returning calls, or a business that refused your refund. South Dakota small claims court handles exactly these disputes — claims up to $12,000 where you have proof the money is owed and the other side won't cooperate.

What Counts as a Viable "Money Owed" Claim

South Dakota small claims court has jurisdiction over money disputes arising from contracts (written or verbal), unpaid services, personal loans, and refund refusals. The key ingredients:

• An obligation to pay — a contract, invoice, loan agreement, receipt, or even a verbal promise with witnesses
• A breach — the payment deadline passed and they didn't pay, or they refused a refund they owe
• An amount at or below $12,000 — if they owe more, you can waive the excess to stay in small claims or file in circuit court

Building Your Case by Claim Type

Unpaid Business Invoice

This is the most straightforward claim. You performed work or delivered goods, sent an invoice, and payment never came.

Evidence the magistrate wants to see:

• The signed contract or written agreement (even an email chain confirming the scope and price)
• The invoice itself, with the due date
• Proof you delivered the work — completion photos, delivery confirmation, email approval from the client
• Your demand letter and any response (or non-response)
• A calculation of what's owed: principal amount plus prejudgment interest under SDCL 21-1-13.1 and 54-3-16(2), generally 10% from the date the loss occurred, unless a lawful contract or invoice rate applies

Personal Loan

Loans between individuals are enforceable in small claims court if you can prove the money was transferred and repayment was expected.

What you need:

• Bank statements or payment app records showing the transfer
• Any written agreement, text message, or email where the borrower acknowledged the loan or agreed to repay
• A timeline showing when repayment was due and what (if anything) was paid back

Verbal loan agreements are legally valid in South Dakota, but harder to prove. Without any writing, you'll need witness testimony or circumstantial evidence (like partial payments that confirm the borrower knew they owed the money).

Refused Refund

A merchant or service provider who contractually owes you a refund and refuses to pay is liable in small claims court. Bring the receipt, the refund policy (check the back of the receipt, the contract, or the company's website), and documentation of your refund request.

Calculating What to Claim

Your claim on form UJS-008 should include:

• Principal amount — the unpaid invoice, loan, or refund amount
• Prejudgment interest — generally 10% per year (SDCL 21-1-13.1 and 54-3-16(2)) from the date the loss occurred, unless a lawful contract rate applies or a different rate is clearly stated on the invoice
• Filing fees and service costs — these are recoverable if you win

Work the interest math before filing. If no different lawful rate applies, on a $5,000 invoice that was due 18 months ago, prejudgment interest at 10% adds $750, bringing your claim to $5,750.

The Demand Letter Step

Before filing, send a written demand letter to the person who owes you. It should state the exact amount owed, the basis for the debt, and a deadline (7 to 14 days is typical) to pay before you file in court.

Send it by certified mail so you have proof of delivery. A demand letter with a signed return receipt documents your attempt to resolve the dispute before filing.

One caution from South Dakota community discussions: don't frame the demand letter as a threat. "Pay me $5,000 or I'll sue" is fine. "Pay me $5,000 or I'll report you to [authority]" starts looking like extortion.

Filing and Service

File in the county where the defendant lives or where the breach, financial loss, or property damage occurred. The clerk sends your paperwork to the defendant via certified mail. Filing fees range from $24.84 to $42.84 depending on the claim amount.

If the defendant is a business, make sure you're suing the correct legal entity — search the Secretary of State's business registry for the LLC or corporation name. Suing a trade name instead of the legal entity can make your judgment worthless at collection time.

At the Hearing

The magistrate will ask you to explain what happened and show your evidence. For an unpaid invoice case, walk through the timeline: when the agreement was made, when you performed, when payment was due, and what you did to collect before filing.

Keep it factual. The strongest unpaid-invoice cases are boring — here's the contract, here's the work, here's the unpaid bill, here's the demand letter they ignored. The magistrate applies the law to the facts.

The South Dakota Small Claims Filing Guide includes an evidence inventory worksheet and a filing-fee calculator so you can build your claim with the right numbers and walk into court with everything organized.

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