Few problems are as corrosive to a small business as a customer who simply will not pay. The work is finished, the invoice is long overdue, and the calls go unanswered. The good news is that California law gives business owners a structured set of tools to recover what they are owed—from a well-crafted demand letter, to an early freeze on the debtor's assets, to a money judgment you can enforce for a decade and renew.

This guide walks through the practical path to getting paid: confirming you have a claim, the deadlines that govern it, the leverage that interest and attorney's fees provide, the pre-litigation demand, your options for filing suit, an underused tool to freeze assets at the outset of the case, and how to actually collect once you win. Our firm handles business and commercial disputes throughout California.

Step 1: Confirm You Have a Claim

Most unpaid-invoice disputes are, at their core, breach-of-contract claims. The elements are well settled: “(1) the existence of the contract, (2) plaintiff's performance or excuse for nonperformance, (3) defendant's breach, and (4) the resulting damages to the plaintiff.” (Oasis West Realty, LLC v. Goldman (2011) 51 Cal.4th 811, 821.) A contract does not have to be a signed, formal document—oral and implied contracts are enforceable in California. An overdue invoice for goods delivered or services rendered will usually support a breach claim along with “common counts” such as an open book account, an account stated, or the reasonable value of goods and services provided.

Step 2: Know Your Deadline

Every claim has a clock, and letting it run out forfeits the debt entirely. For a breach of a written contract, the statute of limitations is four years (Code Civ. Proc., § 337). For an oral contract, it is two years (Code Civ. Proc., § 339(1)). A claim on an open book account also runs four years, generally measured from the date of the last entry. The lesson is simple: do not let an unpaid balance age quietly, and calendar the deadline as soon as the account goes delinquent.

Step 3: Calculate the Real Number—Interest and Fees

The amount you can recover is often larger than the face of the invoice, and that leverage matters in settlement.

Prejudgment interest. When the amount owed is certain or readily calculable, Civil Code § 3287(a) entitles you to interest from the date the debt became due. For a contract that does not specify an interest rate, Civil Code § 3289(b) sets the rate at 10 percent per year after a breach. On an aged receivable, that interest can add up quickly.

Attorney's fees. California follows the “American rule”—each side bears its own fees unless a contract or statute provides otherwise. If your contract contains an attorney's-fees clause, Civil Code § 1717 makes it reciprocal and enforceable, and the prospect of paying your legal bill often brings a reluctant debtor to the table. This is one more reason to put a fee provision in every contract.

Step 4: Send a Demand Letter

A clear, professional demand letter resolves a surprising number of disputes without a lawsuit. An effective demand identifies the debt and its basis, states the total owed including interest, sets a firm deadline, and explains the consequences of non-payment—accruing interest, attorney's fees, and litigation. Beyond its persuasive value, a demand can be required by contract and can help establish your entitlement to fees and interest. (See our guide on demand letters in California business disputes.)

Step 5: Consider a Prejudgment Writ of Attachment

One of the most powerful—and most underused—tools in commercial collections is the prejudgment writ of attachment. Under Code of Civil Procedure § 483.010, attachment is available on a claim of $500 or more based on a contract, where the amount is fixed or readily ascertainable, the claim is unsecured (or the security has little or no value), and, when the defendant is an individual, the debt arises out of that person's trade, business, or profession.

To issue a Right to Attach Order, the court must find that the claim is one on which attachment may be based, that the plaintiff has established the probable validity of the claim, and that the attachment is not sought for an improper purpose. The payoff is significant: attachment lets you place a lien on the debtor's assets at the very beginning of the case—before judgment—which both protects against a debtor dissipating assets and creates intense settlement pressure.

Step 6: File Suit in the Right Forum

If the debt remains unpaid, the size of the claim usually dictates where you file. Small claims court is fast and inexpensive and allows individuals to sue for up to $12,500; business entities are limited to $6,250. Limited civil cases cover claims up to the limited-civil threshold (currently $35,000) and allow full litigation procedures, while unlimited civil handles larger disputes. Where a customer has not merely failed to pay but has wrongfully taken or retained specific property, a conversion claim—and, in appropriate cases, the treble-damages remedy under Penal Code § 496(c)—may also be available, though those theories require more than an ordinary contract default.

(For smaller matters, see our California small claims guide.)

Step 7: Turn Your Judgment Into Money

Winning a judgment is not the same as getting paid; a judgment is a license to collect, not a check. California provides robust enforcement tools: an abstract of judgment that creates a lien on the debtor's real property, writs of execution and bank levies, till taps and keeper levies for cash businesses, and judgment-debtor examinations that compel the debtor to disclose assets under oath. A money judgment is enforceable for ten years and is renewable (Code Civ. Proc., § 683.020), so even a debtor who appears collection-proof today may become reachable later. (Learn more about judgment enforcement in California.)

Practical Tips to Get Paid

• Contract for it up front. Use written agreements that include an attorney's-fees clause, an interest rate, and a venue provision.
• Invoice promptly and document delivery. Keep proof of the order, delivery, and acceptance; it proves performance.
• Act before the statute of limitations. Do not let small balances age into stale, unrecoverable claims.
• Preserve every acknowledgment of the debt. Emails or statements admitting the balance support an account-stated theory.
• Bring in counsel early when the amount justifies it, particularly if attachment could lock down the debtor's assets.

Frequently Asked Questions

Q: The customer never signed anything. Can I still sue?
A: Yes. Oral and implied contracts are enforceable in California, subject to a two-year limitations period. Invoices, emails, and your performance can prove the agreement, and common counts such as an open book account or account stated often apply.

Q: Is it worth suing over a few thousand dollars?
A: Frequently, yes. Small claims court is fast and inexpensive, a contractual fee clause and 10 percent prejudgment interest can make recovery worthwhile, and a judgment remains enforceable for ten years and can be renewed.

Q: How fast can I freeze the debtor's assets?
A: In a qualifying commercial case, a writ of attachment can issue early in the litigation under Code of Civil Procedure § 483.010, and in urgent circumstances on an expedited basis—well before any judgment.

Q: How much interest can I add to the balance?
A: If the amount owed is certain or readily calculable, you are generally entitled to 10 percent per year after the breach under Civil Code § 3289(b), absent a different contractual rate, with the start date governed by Civil Code § 3287.

Q: The debtor says they are “judgment proof.” Should I still pursue it?
A: Often it is still worthwhile. A judgment is good for ten years and renewable, a debtor's finances can improve, and tools like judgment-debtor examinations and property liens can reach assets you cannot see today.

This article is provided for general informational purposes and is not legal advice.

Need help? Contact Kolmogorov Law, P.C. at (909) 235-6116 or visit kolmogorovlaw.com to schedule a consultation with our business litigation team in Irvine, California.