Contractors lose an average of 5 to 10 percent of project revenue to unbilled change orders, work that gets done but never gets invoiced. The money is already sitting on the jobsite. You did the work, bought the material, and paid your guys. You just never collected it. This tutorial walks you through a contractor change order system that plugs that leak, from the moment scope changes on a job to the moment payment hits your account.
Key takeaways
- Unbilled change orders are not an administrative problem. They are a cash leak. Treating them that way changes how you prioritize the fix.
- Every change order needs a paper trail started before the work begins, not after.
- Client sign-off does not have to be slow. A photo of a signed handwritten note, or a text reply saying "approved," documented in writing, is legally defensible in most states.
- A simple daily log, reviewed at end of shift, catches 90 percent of scope drift before it becomes a loss.
- The right system takes less than ten minutes a day to run.
What is an unbilled change order, and why does it keep happening?
An unbilled change order is any work you perform outside the original contract scope that you never bill for. It is not always a big ticket item. More often it is the accumulation of small things: an extra circuit run because the homeowner decided to add a bathroom fan, a reroute on a drain line because the inspection uncovered rotted blocking, a thermostat upgrade the GC asked for verbally while you were standing in the mechanical room.
Each of those changes might be $200 to $800 on its own. On a six-week remodel with a three-person crew, those small changes stack fast. Hit five or six per week and you are looking at $4,000 to $8,000 in unbilled work by the time you close out the job. That is not a rounding error. That is a truck payment.
The reason it keeps happening is simple: the moment of the change is the worst possible moment to stop and write it up. You are mid-task, the client is standing there wanting an answer, and stopping to document feels like it slows the job. So you make a mental note, tell yourself you will write it up later, and later never comes.
A contractor change order system fixes this by removing the friction from capture and sign-off. When it costs you almost nothing to log a change in real time, you actually do it.
Prerequisites: What you need before you build this system
Before you start, get three things in place.
A change order clause in your contract. Your contract needs to say, explicitly, that any work outside the original scope requires a written change order before work begins and will be billed at your standard rates. If you do not have this language, clients will dispute your invoices. A single sentence will do: "Any changes to the contracted scope of work will be documented in writing, signed by both parties, and billed separately at the rates stated in this agreement."
A standard rate sheet. Know your numbers before the job starts. A 200-amp panel upgrade runs $2,800 to $4,500 installed depending on your market. A water heater swap is $900 to $1,800. A furnace filter access door cut-in might be $150. When you know your rates cold, you can price a change order in two minutes instead of twenty.
A place to capture changes in the field. This does not have to be software. A dedicated notebook in your truck, a shared notes folder on your phone, or a field app all work. What does not work is "I'll remember it." Pick one place and use it every time.
Step 1: Identify scope changes in real time, not at end of job
The first step in how to bill change orders correctly is catching them when they happen. Scope changes fall into three categories.
| Category | Example | Average Value |
|---|---|---|
| Client-requested additions | "Can you also add an outlet over here?" | $85 to $400 |
| Field conditions discovered during work | Rotten subfloor found under tile | $300 to $2,500 |
| GC or super verbal requests | "Run a dedicated circuit for the compressor" | $200 to $900 |
Train yourself to stop when you hear any of the following: "while you're at it," "can you also," "we decided to change," or "the inspector said." Those phrases are change order triggers. Every time you hear one, the next thing out of your mouth is: "Sure, let me write that up so we're on the same page about cost and timing."
That sentence is not confrontational. It is professional. It tells the client you take the job seriously. And it starts the documentation clock.
Step 2: Document the change before the work begins
A construction change order is a written record of what work is being added or changed, what it costs, and who approved it. It does not need to be a formal printed form. It needs to include four things:
- Job name and date
- Description of the additional work (specific enough that a stranger could understand it)
- Price, broken down into labor and material if your contract requires it
- Client or authorized contact signature
On a service call or remodel, this can be a handwritten half-sheet. Take a photo of it the moment it is signed. That photo goes into the job folder on your phone. Done.
If you are using field software, fill in the same four fields and email or text the client a PDF link. Most clients will approve via text reply within ten minutes. Screenshot that reply and save it to the job file. In most states, a written text exchange constitutes a valid authorization. Consult your attorney to confirm this applies in your jurisdiction.
The non-negotiable rule: no work starts until you have authorization documented. This is harder than it sounds on a busy job, but it is the only rule that actually protects you. An undocumented verbal approval is worth nothing when the client disputes the invoice sixty days later.
Step 3: Price the change order correctly the first time
Pricing errors on change orders are the second biggest reason contractors under-collect. You either forget to include material markup, you forget to account for the time lost to mobilization, or you underprice labor because you are trying to keep the client happy in the moment.
Use this structure every time:
| Line Item | How to Calculate |
|---|---|
| Material cost | Your actual cost, plus your standard markup (typically 15 to 25 percent) |
| Labor hours | Realistic estimate, not optimistic. Add 15 percent for setup and cleanup. |
| Labor rate | Your fully burdened rate, including payroll taxes and insurance |
| Overhead allocation | A flat percentage, typically 10 to 15 percent of labor and material |
| Profit margin | Whatever your standard markup is. Don't discount change orders. |
Change orders should not be priced at cost-plus out of guilt. You are mobilized on that job. The client is already getting the benefit of your overhead already on site. Price it like the real work it is.
A concrete example: an HVAC tech gets asked to add a programmable thermostat and run new wiring to a second zone while he is already in the mechanical room. Material might be $340 for the thermostat and wire. Labor is two hours at $95 burdened rate. Overhead at 12 percent adds $51. Margin at 20 percent adds $113. Total change order: $647. If he does that work without writing it up, he just donated $647 to the project.
Step 4: Build a daily change order log
A daily change order log is a five-minute end-of-shift habit that catches everything you approved or discovered during the day. Before you leave the site, review the day and ask yourself three questions:
- Did anything get added to our scope today?
- Did we find any conditions that created extra work?
- Did the GC, owner, or super ask us to do anything not in the original contract?
If the answer to any of those is yes and you do not have a signed change order in your job file, write it up immediately. Text it to the client or owner. Get approval tonight, before tomorrow's work continues.
Run this log daily, not weekly. By the end of the week, the details are fuzzy. By the end of the job, they are gone entirely.
Step 5: Invoice change orders on their own line, immediately
The fastest way to lose a change order is to bundle it into the final invoice six weeks after the work happened. Clients forget. They dispute. They feel like they are being surprised.
Bill change orders separately, on their own invoice, as close to approval as possible. For service work, bill the same day the work is done. For a remodel or commercial job with a draw schedule (a draw schedule is a billing schedule tied to project milestones, agreed on before the job starts), invoice approved change orders with each draw.
When you invoice promptly, two things happen. The work is fresh in the client's mind, so disputes drop. And you improve your cash flow because you are collecting continuously instead of front-loading all your risk to the final invoice.
Troubleshooting: When the system breaks down
Client refuses to sign before work starts. Hold the work. Politely but clearly say: "I want to get this done for you. I just need your authorization in writing first so we're both covered." If the client refuses and you proceed anyway, you have already lost the change order.
GC says "just do it and we'll sort it out later." Get it in writing before you start. "Sort it out later" almost always means you eat it. A text to the GC saying "confirming we're adding X for Y dollars, please reply to approve" takes thirty seconds and creates a paper trail.
You forgot to write up a change order and the work is already done. Write it up now. Send it with a note that says "Here is the documentation for the additional scope we completed on [date]. Please review and approve." Most clients will sign. Some will push back. Either way, you are in a better position than if you never sent it.
Client disputes the price after approving. Show them the signed change order or the text thread. Keep your voice level. The documentation is your answer.
Frequently asked questions
How do I bring up change orders without sounding like I'm nickel-and-diming the client?
Frame it as protection for both of you, not just for you. Say: "I want to make sure we're both on the same page so there are no surprises at the end." Most clients respond well to that. The ones who don't, who push back on any documentation, are the same clients who dispute your final invoice. The change order process tells you early who you are dealing with.
Do I need a formal printed form, or can I do change orders by text and email?
You do not need a printed form. A text exchange that clearly describes the work and price, with a reply from the client confirming approval, is documented authorization in most states. The key is to state the scope and price in writing and get an explicit reply, not just "sounds good" to a verbal conversation.
How do I handle change orders on a time-and-material job?
On T&M work, every hour and every material purchase is already a change order in a sense, because the scope is open. Still document any changes to the project direction or owner-requested additions separately. It protects you if the client later claims a task was outside what they asked for.
What's the difference between a change order and a punch list item?
A punch list item is work that was part of the original contract but was not completed correctly or at all. A change order is work that was never in the original contract. Do not let clients reclassify your change orders as punch list items to avoid paying. If it was not in the original scope, it is a change order.
How do I get clients to approve change orders faster so the job doesn't stall?
Make approval as easy as possible. Send a short PDF or a simple text. State the price clearly. Tell them how long you need to wait before the job stalls. Most clients approve within the hour if the request is clear. If you are waiting more than a day on a routine change, call them directly. Do not let a $400 change order hold up a $40,000 job.
Can I charge for the time it takes to write up a change order?
Yes, and on complex changes you should. If a change order requires field measurement, material research, or significant estimating time, that is billable. Most contractors do not charge for simple change orders but do include a project management or administration line on larger ones.
What if the client only verbally approved and now they're denying it?
This is why documentation matters before the work starts, not after. If you have nothing in writing, you are in a difficult position. You can use photos timestamped on the day of the work, text threads showing the conversation, or testimony from a crew member who witnessed the approval. None of those are as clean as a signed change order. Document it real time, every time.
Closing summary
Unbilled change orders are not an accounting problem. They are a field problem, and the fix is a field habit. Catch scope changes when they happen. Write them up before the work starts. Price them correctly. Get authorization in writing. Bill them promptly. Review your log every single day before you leave the site. Do that consistently and you will collect the money you have already earned.
Contractors who build this system into their daily routine typically recover thousands of dollars per job they were previously leaving on the table. The paperwork is not the enemy. The habit of skipping it is.
If the documentation side of your business, writing up change orders, sending invoices, and chasing approvals, is eating into time you should be spending in the field, Krue is built to handle exactly that. It captures scope changes by voice, turns them into invoices, and follows up on payment so you don't have to.
