Unpaid Invoice WA Small Claims — How to Sue for Payment in the Magistrates Court

A client owes you money. The invoice is overdue, follow-up emails go unanswered, and phone calls hit voicemail. For a sole trader or small business, an unpaid invoice under $10,000 isn't just an accounting problem — it's rent, stock, and wages you can't cover. Here's how to recover it through the WA Magistrates Court.

Confirm Who You're Suing

Before you file anything, get the debtor's correct legal identity. Filing against the wrong entity means your judgment is unenforceable — even if you win.

• If they're a sole trader: Sue them by their personal legal name, adding "trading as [business name]." Check the ABN Lookup to confirm.
• If they're a partnership: Name each partner individually, "trading as [firm name]."
• If they're a company: Use the exact registered name from an ASIC company extract, including "Pty Ltd" and the ACN. Don't guess — a current company extract costs $9 and gives you the registered name and registered office address where you'll serve the claim.

Send the Letter of Demand

Write a formal letter setting out the invoice number, amount owed, due date, and a 7- to 14-day deadline to pay. State that you'll file a minor case claim in the Magistrates Court of Western Australia if payment isn't received.

Send it by registered post. Keep the Australia Post receipt and online tracking confirmation — this becomes evidence that you tried to resolve it before court.

File Form 4 on the eCourts Portal

Once the demand period expires without payment, file a Form 4 Minor Case Claim through ecourts.justice.wa.gov.au.

In your statement of claim, set out:

1. When the work was performed or goods supplied
2. The invoice amount and when it was due
3. That payment hasn't been received despite the demand letter
4. The total you're claiming, including the filing fee and any pre-judgment interest your contract entitles you to

If the claimant is a small business that meets the definition, lodge the small business declaration (Form 1) to pay the $196.50 eligible-entity fee instead of the $384.00 standard entity fee.

Serve and Wait

Serve the sealed Form 4 on the debtor — personally for individuals, by post to the registered office for companies. The debtor has 14 days to respond (21 if they're interstate).

If they don't respond, apply for default judgment using Form 13. For a liquidated debt like an unpaid invoice, the registrar can grant judgment on the papers — no hearing required.

If they do respond and dispute the claim, the registrar lists a status conference before a Magistrate, who helps the parties explore settlement and manages the case. If it does not settle, the matter may proceed to trial before a Magistrate.

Collecting the Money

A court judgment proves the debt is owed, but it doesn't force payment. If the debtor still doesn't pay after judgment, enforcement options under the Civil Judgments Enforcement Act 2004 include means inquiries (examining the debtor's finances under oath), property seizure orders, and earnings appropriation orders. An earnings appropriation order is available only after a previous instalment order was disobeyed and cancelled.

The WA Minor Case Claim Guide walks through the entire recovery process from demand letter to enforcement, with claim calculation worksheets designed for sole traders and small businesses.

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