Most unpaid invoices are not fraud. They are forgetfulness, confusion, cash flow problems, or a dispute nobody told you about. Working through them in the right order recovers the large majority without anything escalating — and the order matters, because every step burns a little goodwill you cannot get back.
Step 1: check it is not you
Before anything else: did the invoice go to the right person, at the right address, with the right PO, matching the signed estimate? A surprising share of “won’t pay” turns out to be “never received it” or “it doesn’t match what we approved, so it is sitting in a query pile.”
Step 2: a friendly, specific reminder
Three days past due. Short, warm, and carrying the invoice again — never just “payment is overdue.” Include the amount, the invoice number, and a link to pay. Assume it was missed, because usually it was.
Step 3: pick up the phone
Around day 10. Email makes ignoring easy; a call makes it a conversation. The question to ask is not “when will you pay” but “is there a problem with the invoice?” If there is a dispute, you want to know now, and you want to be the person who asked rather than the person who assumed.
Step 4: offer a payment plan before you escalate
If the honest answer is that they cannot pay right now, half of something beats all of nothing six months later. Put the plan in writing, with dates and amounts, and have them confirm it. This is also useful evidence later if it comes to that.
Step 5: formal written demand
Around day 30. Plain and unemotional: the work, the amount, the date due, the previous attempts to contact, the late fee if disclosed, and a deadline. Say what happens if the deadline passes. Send it in a way you can prove was delivered.
Step 6: the legal routes
- Mechanic’s lien. The strongest tool a contractor has — but it has hard deadlines, usually measured from last day on site, and they are short. Miss the window and the right is gone. Check your state’s rules before you need them, not after.
- Small claims court. Cheap, no lawyer needed, with limits commonly between $5,000 and $15,000. Bring the signed estimate, the change orders, the invoice, photos and your contact log.
- Collections. Typically 25–50% of what is recovered. Reasonable on an old debt you have written off mentally, poor value on a fresh one.
What decides whether you collect
Not persistence — paperwork. A signed estimate, signed change orders for everything that grew, dated photos, and an invoice that matches. With those, most of these steps end at step two or three. Without them, you are arguing about memory, and memory does not win.
Build the evidence as you go
Toolbelt estimates are accepted with a typed signature, timestamped on the document; the invoice is built from that same accepted estimate so the numbers cannot drift; and photo reports give you dated, captioned evidence of the condition you found. Three free estimates, no card.
Prevention is cheaper: payment terms, change orders, and deposits.