You did the extra work. The client approved it. Now the hard part: getting it onto an invoice in a way the client recognizes, agrees with and pays. Most of that comes down to timing, a clear invoice line and a running total the client has already seen.
01When to bill a change order
The short answer: bill an approved change order on the very next invoice or draw after it's approved, as its own line, with its own number. Not at the end of the job. Not rolled into "misc." Not "we'll settle up later."
Every week a change sits unbilled, it gets harder to collect. The client forgets the conversation, the price starts to feel like a surprise, and the extra work quietly turns into something they assume was included. Billing promptly keeps the change tied to the moment the client asked for it and said yes.
Three common billing timings
| Timing | How it works | Good fit for |
|---|---|---|
| Paid on approval | The change order is approved and paid (in full or a deposit) before the changed work starts. | Changes with special-order materials, big upgrades, or clients who are slow to pay. |
| Next draw or progress invoice | The approved change is added to the next scheduled invoice as its own line. | Most mid-size changes on a job that already bills in draws. |
| Billed at completion of the change | You invoice the change by itself as soon as that piece of work is done. | Time-and-materials changes where the final cost isn't known until it's built. |
What doesn't work well is holding every change for the final invoice. That's the bill where clients are most likely to push back, because it's also where the retainage, the punch list and any frustration with the job all land at once.
Whichever timing you use, write it on the change order itself. The template in our free change order template article has a "Payment due" line with three boxes for exactly this reason: on approval, next draw, or other.
02Get these right before you invoice
Billing problems usually start before the invoice. If any of these are missing, fix them first, because the invoice will only be as solid as the paper behind it.
- Written approval. A signature, an e-signature, or a written reply that names the change order number, depending on what your contract and your state allow. No approval, no invoice line, because there's nothing to point to if the client asks why it's there.
- A clear price. A fixed amount, or time-and-materials rates written on the change order. "We'll figure it out" isn't a price.
- A change order number. CO-01, CO-02, or a job prefix like CO-KIT-03. The same number goes on the form, your log, the approval message and the invoice line.
- The running contract total. Original contract + prior approved changes + this change = new contract total. If the client has already seen that number, the invoice won't surprise them.
- Days added, even if zero. Not a billing item, but it heads off "you're behind schedule" pushback when the invoice arrives.
If you're not sure whether something even counts as a change order or is part of your base scope, read change order vs. scope creep first. And if your problem is the number itself, how to price extra work on a remodel walks through it line by line.
03How to show change orders on the invoice
A good change order invoice answers the client's three questions without a phone call: what is this, did I approve it, and how does it change what I owe in total?
One line per change order
List each approved change as its own line with the CO number and a short description that matches the change order. "CO-KIT-03: Add 20A outlet at bar wall, approved [date]" is easy to recognize. "Electrical extras" is not.
Show the contract summary
Add a small summary block to every invoice once the job has changes. Here's a simple layout.
Example numbers only. Use your own contract amounts.
Credits for deleted work go in the same list with a minus sign. Showing credits openly builds trust, and it keeps the running total honest.
Attach the approval
Attach a copy of the signed change order or a screenshot of the written approval to the invoice, or link to it in your PM software. It takes seconds and answers "I don't remember agreeing to that" before it's asked.
If you bill in progress draws
Many remodelers bill in stages: deposit, rough-in, drywall, and so on. Some use a schedule of values, where each line of the contract has a value and you bill a percentage complete. Either way, the cleanest approach is to add approved changes as new lines, separate from the original lines, rather than quietly bumping up an existing line. That keeps the original contract visible and makes it obvious what changed and why.
Free download
Get the free clause and approval text
A sample "changes to the work" clause to take to your attorney, the "let me write it up" script for clients, crew and subs, and the approval text you can save as a phone shortcut.
04How to collect without a fight
Most collection problems on change orders aren't about the client refusing to pay. They're about surprise. These habits take the surprise out.
Say the billing timing out loud
When you send the change order, say when it will be billed. In the approval text: "Once approved, this goes on your next progress invoice as CO-04." Then the invoice is just the thing you already said would happen.
Use a deposit for special orders
If a change requires special-order materials that you can't return, consider asking for those material costs on approval. Write it on the change order: "Materials deposit of $[__] due on approval; balance on next draw." Whether you can require a deposit, and how much, can be regulated in some states for home improvement work. Ask your attorney what applies where you work.
Follow the same steps every time
- Due date passes: a friendly reminder that names the CO number and links the approval.
- A week later: a phone call. Ask if there's a question about the change. Sometimes there is, and it's easier to fix on the phone.
- Still unpaid: follow what your contract says about late payment, which may include pausing work. Don't improvise this step.
Late fees, stopping work and lien rights all depend on your contract and your state's rules, and many states have strict notice deadlines for liens. Have a local construction attorney walk you through what applies before you need it, not after.
05Common change order billing mistakes
| Mistake | What to do instead |
|---|---|
| Saving every change for the final bill | Bill each approved change on the next invoice or draw. |
| Lumping changes into "extras" or "misc." | One line per change order, with the CO number and a matching description. |
| Billing work that was never approved in writing | Get the approval first. If the work is already done, send the change order now and explain it plainly. |
| Hiding credits | Show deleted work as a credit line in the contract summary. |
| Editing original contract lines | Add approved changes as new lines so the original contract stays visible. |
| No running total | Show the revised contract total on the change order and on every invoice. |
06A simple system: log, invoice, reconcile
You don't need new software for this. You need one list that every change goes through. A spreadsheet works; so does the change order feature in Buildertrend, JobTread or whatever you already use.
Your change order log needs these columns:
- CO number and job
- Short description
- Amount (and credit, if any)
- Days added
- Status: Draft, Sent, Approved, Declined
- Date approved and how (signature, e-sign, written reply)
- Invoice number it was billed on
- Date paid
Once a week, take five minutes and look for two things: anything Approved with no invoice number, and anything Sent with no answer. The first is money you've earned and haven't asked for. The second is work your crew might be about to do without approval.
If typing up change orders is what slows you down, AI can draft them from a voice note in a couple of minutes. Our practical AI prompts for residential contractors include a change order prompt and an invoice-line prompt you can copy.
The AI Change Order Pack · $47
The whole workflow, ready to copy
A 20-page guide plus an editable .docx change order template. You get 10 copy-paste prompts, a phone-only manual setup, an optional automated setup, client approval texts and emails, a pricing-the-change checklist and sample clause language for your attorney to review. One-time price.
07FAQ
Can I bill a change order before the work is done?
Often, yes, if your contract and the change order say so, for example a deposit on approval for special-order materials. Some states regulate deposits and advance payments on home improvement work, so check with a local construction attorney.
What if the client disputes a change order on the invoice?
Start with the paper: the signed or written approval, the CO number, and the price on the form. Most disputes are memory problems, and the approval settles them. If there was no written approval, talk it through, and use it as the reason to never skip one again.
Should change orders be on a separate invoice?
Either works. A separate line on your regular progress invoice is simpler for most remodelers. A separate invoice can make sense for a large change paid on approval. What matters is the CO number, the description and the running total.
How do I handle a time-and-materials change?
Put your rates and markup on the change order before the work starts, plus a not-to-exceed amount if the client wants one. Track the hours and receipts, then bill the actual total with the backup attached.