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To collect an unpaid invoice, work up a ladder and stop at the first step that gets you paid. Check the invoice reached the right person and was correct. Send a polite reminder the day after it is due. Call after a week. At 14 days, pause any further work and put it in writing. If cash is the client's problem, agree instalments. At 30 days, send a formal demand letter with a deadline. Only then choose a last resort: a collection agency, which typically keeps 20% to 50% of what it recovers, or small claims court, where filing costs as little as $30 to $100 in some states. Before you escalate, compare what each step costs with what you are owed.
If you have an invoice nobody has paid, you are in the majority. According to QuickBooks' 2026 late payments research, 59% of small businesses were carrying an invoice at least 30 days past due (47% the year before), and the average amount owed to those businesses was $17.7K.
Most of that money comes in without a fight, as long as you follow up in the right order. This guide gives you the seven steps, what each one costs, how to decide whether an invoice is worth chasing, how small claims court works, and how to find every unpaid invoice in QuickBooks.
How to Collect an Unpaid Invoice in 7 Steps
- Check the invoice before you chase it. Confirm it went to the person who actually pays, that the amount and due date are right, and that any purchase order number the client needs is on it. Some "late" invoices are simply sitting in the wrong inbox.
- Send a polite reminder the day after the due date. Keep it short, attach the invoice again, and include a payment link. "Just a reminder that invoice #142 for $2,400 was due yesterday. A copy is attached, and you can pay here."
- Call after 7 days. A phone call to whoever approves payments often finds the real problem in two minutes: a missing approval, a changed contact, a question about one line of the invoice.
- At 14 days, pause work and put it in writing. If you are still working for the client, stop starting new work until the invoice is paid, and say so politely in an email. Continuing to deliver only increases what you are owed.
- Suggest instalments if cash is the client's problem. Two or three smaller payments on fixed dates are better than one large payment that never arrives. Confirm the plan in writing, with dates and amounts.
- At 30 days, send a formal demand letter. Include the invoice number, how much is owed and since when, a final deadline (usually 7 to 14 days), and exactly what you will do if it passes without payment. Send it by email and by tracked mail so there is a record.
- Choose a last resort. Hand the debt to a collection agency, file in small claims court, or write it off. Which one makes sense depends on the amount, which the cost section below works through.
Aziz's take: The step most people skip is the first one. Before you send anything firm, check the invoice actually reached the person who pays. Chasing the wrong inbox for a month and then sending a demand letter is how a good client turns into an awkward one.
- Remind Days 1 to 7 Check the invoice, send a reminder, then call.
- Escalate Days 14 to 30 Pause work, put it in writing, suggest instalments.
- Formalize Day 30 onward A demand letter with a final deadline.
- Enforce After the deadline Collection agency, small claims court, or write it off.
What Each Way of Collecting Costs
The first three stages cost little more than your time. The last stage is where real money goes, and the options work very differently.
| Option | What it costs | Best for | Watch out for |
|---|---|---|---|
| Reminders and calls | Your time | Every unpaid invoice, first | Waiting too long before the first reminder |
| Payment plan | Waiting longer for the full amount | A client who wants to pay but cannot all at once | Agreeing a plan without dates in writing |
| Demand letter | Free if you write it yourself; a lawyer charges for one on letterhead | Any invoice past 30 days | Threatening a step you will not actually take |
| Collection agency | Usually a contingency fee of 20% to 50% of the amount collected, higher the older the debt | Larger debts, or clients who have stopped replying | The relationship is over once an agency is involved |
| Small claims court | A filing fee, for example $30 to $100 in California, plus your time | Debts under your state's limit, with a clear paper trail | Winning a judgment is not the same as being paid |
When Is an Unpaid Invoice Worth Chasing?
Compare what you would actually receive with what it costs to get it. Three illustrative invoices, assuming an agency fee of 30% (inside the usual 20% to 50% range) and California's small claims rules:
| $800 invoice | $4,000 invoice | $20,000 invoice | |
|---|---|---|---|
| Through an agency | You keep about $560, if it collects. Some agencies will not take small debts on contingency | You keep about $2,800 | You keep about $14,000 |
| Small claims (California) | Filing fee of $30 to $100, and a day of your time | Filing fee of $30 to $100, and a day of your time | Over the $6,250 limit for businesses, so not an option |
| Sensible route | Steps 1 to 6, then small claims or write it off | Steps 1 to 6, then small claims | Steps 1 to 6, then an agency or a lawyer |
Two things to weigh beyond the money. First, the relationship: once you use an agency or a court, that client will rarely work with you again, which matters if they send you regular work. Second, your time: a day spent preparing for court has a cost too, and on small invoices it can be most of what you would recover.
How to Sue for an Unpaid Invoice in Small Claims Court
Small claims court is built for exactly this kind of dispute, and in many states you represent yourself. The details vary by state, so check your own court's rules, but the process usually looks like this:
- Check the limit. Every state sets a maximum claim. In California it is $6,250 if you are suing as a business and $12,500 for individuals.
- Send the demand letter first. Courts often expect you to have asked for payment before you file, and the letter is part of your evidence.
- File the claim in the court for the area where the client is based or where the work was done, and pay the filing fee. In California it is $30 to $100, and you can ask for a fee waiver if you cannot afford it.
- Serve the client with the claim, following the court's rules on how it must be delivered.
- Bring your paper trail to the hearing: the contract or quote they accepted, the invoice, proof the work was delivered, and every reminder you sent.
Winning gives you a judgment, which is a court order that the client owes you. If they still do not pay, collecting on the judgment is a separate step, and the court can tell you what options your state allows.
How to Find Unpaid Invoices in QuickBooks
In QuickBooks Online, go to Reports and look in the "Who owes you" group. The Open Invoices report lists every unpaid invoice with a total for each customer. The Accounts receivable aging summary shows the same balances grouped by how late they are, which is the more useful view for deciding who to chase first.
Both reports rely on every customer having payment terms set, so add terms to any customer that is missing them. Menu names vary slightly between versions and regions, but the report names are the same.
How to Stop Invoices Going Unpaid
The cheapest collection step is the one you never need. Three habits prevent most of it:
- Agree payment terms in writing before the work starts. A signed freelance contract that states when and how you are paid is what makes a demand letter or a court claim straightforward later.
- Ask for money before or during the work, not only after. A deposit and staged payment milestones mean you are never owed more than one stage of work at a time.
- Forecast the gap. A 13-week cash flow forecast shows you weeks ahead when a late payer would leave you short, so it becomes a plan instead of a surprise.
Aziz's take: Decide your collection rules before you need them, the same way you decide your prices. If you already know that day 14 means work pauses and day 30 means a demand letter, you stop agonizing over each late client and just follow the schedule.