How Contractors Can Use AI to Chase Unpaid Invoices
By Stacey Tallitsch | September 10, 2026
You finished the job three weeks ago. The customer was happy. The invoice went out. And the money still is not in your account.
If you run a contracting business, you know this feeling. You are good at the work. You are less good at chasing people for payment. There is no office manager to do it for you. So the follow-up sits on your list until you get a slow afternoon, which never comes.
You are not alone in this. A 2025 report from Intuit QuickBooks on small business late payments found that 56% of small businesses are owed money on unpaid invoices, with the average business waiting on about $17,500. Nearly half had invoices more than 30 days late. Late payment is not a sign you run a sloppy shop. It is just what happens when one person does the estimating, the labor, and the billing.
This post walks through how AI can handle the follow-up for you. Not your whole billing system. Just the annoying, repeating part where someone has to send a polite reminder at the right time.
What AI actually does here
Let me be clear about what we mean by AI in this case, because the word gets thrown around loosely.
Two different things can help you, and they are not the same.
The first is automation built into the invoicing software you may already use. This is not fancy AI. It is a rule you set once: if an invoice is not paid, send a reminder. The software watches the clock and sends the email so you do not have to.
The second is an AI writing tool, like ChatGPT or Claude. These are programs that write text for you when you ask. You use them to write the actual reminder, so it sounds firm but friendly, instead of you staring at a blank screen wondering how to word it.
Most contractors get the best result using both. The software handles the timing. The AI writing tool handles the wording. Here is how to set that up.
Step 1: Turn on reminders in the software you already have
If you invoice through QuickBooks, Jobber, or Housecall Pro, you already have automatic reminders sitting there unused. Most operators never switch them on.
In QuickBooks Online, you open your settings, go to the Sales tab, and turn on automatic invoice reminders. You can schedule up to three of them. The company's own guide to automatic invoice reminders walks through the exact screens.
A simple schedule that works for most contractors:
- One reminder 3 days before the invoice is due
- One reminder the day after it is due
- One reminder 7 days after it is due
That is it. The software now chases every invoice on its own, on the same schedule, every time. You stop being the bottleneck.
If you do not use invoicing software yet, this is a good reason to start. A basic plan from any of the tools above costs less than one unpaid invoice, and the reminders alone often pay for it.
Step 2: Write better reminders with an AI tool
The default reminder text in most software is stiff and forgettable. This is where an AI writing tool earns its keep.
Open ChatGPT or Claude. Both have free versions that are fine for this. Then ask it to write your reminders. A prompt is just the instruction you type in. Here is one you can copy:
Write three short invoice reminder emails for my contracting business. The first is a friendly heads-up before the due date. The second is a polite note the day after it is due. The third is firmer, for when it is a week late. Keep each under 90 words. Sound like a real person, not a law office.
You will get three drafts in a few seconds. Read them. Fix anything that does not sound like you. Then paste them into the reminder settings in your software. You write them once and they send for months.
Here is the kind of first reminder the tool should hand back:
Hi [customer name], quick heads-up that your invoice for the work at [job address] is due in 3 days. You can pay using the link at the top of the invoice. Any questions, just reply here or give me a call. Thanks again for the work.
Short, warm, and clear about how to pay. That last part matters. Plenty of late payments are not refusals. The customer set the invoice aside and forgot how to send the money.
If you want the reminders to feel personal, ask the tool to leave blanks like [customer name] and [job address] that your software fills in for you. Most invoicing tools support these fill-in fields.
Step 3: Handle the awkward late ones by hand, with help
Automatic reminders clear most of your late invoices. Some customers still go quiet. That last group needs a real message from you, and those are the ones people dread writing.
You do not have to write them cold. Paste the situation into your AI tool and let it draft the message. For example: a customer owes me $4,200 for a roof repair finished five weeks ago, two reminders went unanswered, write a short and firm and professional message asking for payment or a phone call this week.
You will get a solid draft. You stay in control. You read it, adjust the tone, and hit send yourself. The AI removes the hard part, which is finding the first sentence when you are annoyed.
What could go wrong
A few honest warnings, because this is not magic.
The AI can get facts wrong. It does not know your customer or the real balance owed. It only knows what you tell it. Always read the message and check the numbers before it goes out. Never let it send anything on its own without your eyes on it first.
The tone can drift too formal or too casual. Read every draft the first few times. Once you have wording you like, save it and reuse it. You do not need to generate fresh text every day.
One more thing: do not stack up too many reminders. Three is plenty. A customer who gets a message every single day stops reading them, and you start to look desperate instead of professional.
And reminders will not fix a customer who simply cannot pay. AI speeds up the polite part of collections. It does not replace a phone call, a lien, or a talk about a payment plan when a job goes truly sideways.
What to expect after you set this up
The setup takes about an hour, one time. Turning on software reminders is 15 minutes. Writing your three messages with an AI tool is another 15. The rest is testing.
The cost is close to nothing. The reminder feature is already included in invoicing software you pay for. The AI writing tools have free versions that cover this use easily.
What changes is your week. You stop carrying a mental list of who owes you. The reminders go out on their own, on time, every time, worded the way you would word them. Most contractors who do this see their late invoices shrink within a month or two, simply because customers are getting nudged consistently instead of whenever the owner remembers.
If you have not set up the front end of your billing yet, it is worth reading how contractors can use AI to write estimates faster so the whole path from quote to payment moves quicker. If missed calls are also costing you jobs, the same plain approach fits answering every call with an AI receptionist. And it helps to know the difference between a basic chatbot and the real AI tools so you spend money on the right thing.
Getting paid on time is not a technology problem. It is a follow-up problem. AI happens to be very good at follow-up. Let it do the part you keep putting off, and keep your own hours for the work only you can do.
-- Stacey | The Standalone
About the Author
Stacey Tallitsch runs The Standalone, an AI Implementation Diagnostic practice for small business owners. He has 30 years of experience in technology and has written 21 books on systems thinking and decision-making. More than 30,000 students have learned from his online courses.
- Stacey Tallitsch, The Standalone