Most change order disputes aren't about whether the work happened — they're about whether the work was authorized. "Client said to add it" is not a defense. "I have an email from the client approving it" is.
Writing a change order correctly is one of the highest-leverage things a contractor can do. It takes five minutes. Getting out of a dispute over an unauthorized change takes weeks and often ends with you eating the cost.
This guide covers: what fields a change order must have, why verbal authorizations don't hold up, the exact script for the homeowner conversation, and what to do when the client won't sign.
Why Verbal Change Orders Cost You Money
The scenario: client says "while you're at it, can you also run a line to the garage?" You say "sure." You add the work, include it in your final invoice, and the client refuses to pay because "that wasn't in the contract."
Your options at this point:
- Fight it in small claims court with no documentation
- Offer a discount to make it go away
- Eat the cost
None of these are good.
The fix isn't harder — it's a five-minute form before you start the work.
What a client saying "go ahead" actually means in legal terms: nothing, unless there's a record. Courts look for offer, acceptance, and consideration. "Add the outlet" is the offer. "Sure" is the acceptance. But "sure" via a text message without any scope, price, or timeline attached? A lawyer will eat that alive.
The contractor's discipline is simple: Before you start any work outside the original scope, get a written change order signed or a written approval via email. That's it.
The 7 Fields Every Change Order Needs
A change order that holds up has seven elements. Missing any of them creates a gap a client can exploit.
1. Project and Contract Reference
The header of every change order should tie it to the original contract:
- Project name and address
- Original contract number and date
- Change order number (sequential: CO-001, CO-002, etc.)
- Change order date
When you're three change orders deep on a job and you're filing a lien, the documentation has to show that each change order is an amendment to a specific, dated contract. Without the reference, it's just a standalone document.
2. Description of the Change
Write what actually changed, specifically. Not "additional electrical work." Something like:
Install dedicated 20A circuit to garage subpanel, per owner request. Includes: (1) 50ft run of 12/2 NM wire from main panel breaker #18, (2) surface-mount subpanel in garage (120V, 4-space), (3) single GFCI outlet at workbench location, (4) framing repair at point of entry.
Be specific enough that a third party could read this description and understand exactly what was done. Vague descriptions create disputes. Specific descriptions close them.
3. Cost Impact
Break it down by line item:
| Item | Qty | Unit Cost | Total |
|---|---|---|---|
| Labor (hours × rate) | X | $X/hr | $XXX |
| Materials (itemized) | — | — | $XXX |
| Permit or inspection fees | — | — | $XX |
| Markup % | — | — | $XX |
| Change Order Total | $XXX | ||
Don't bundle everything into "additional work: $800." Clients challenge line-item totals. If you can show hours, rates, and material costs, your pricing is defensible.
4. Schedule Impact
Write the schedule impact in calendar days:
This change order adds 2 calendar days to the project schedule. New substantial completion date: [date].
If it adds zero days, write "No schedule impact — 0 additional calendar days." Don't leave this blank. A blank schedule impact is a gap in the document that a client can fill with a claim that the work delayed them.
5. Revised Contract Total
Show the math:
| Original contract value | $XX,XXX |
| This change order | +$X,XXX |
| New contract total | $XX,XXX |
6. Payment Terms for the Change
State when payment for this change order is due:
- "Due upon approval of this change order"
- "Due upon completion of this change order work"
- "Due at final invoice / project close"
If the change order adds significant cost (over $1,000), consider requiring partial payment before the work starts. This is standard for larger change orders on commercial projects.
7. Signature and Date Lines (Contractor + Client)
This is the non-negotiable field. No signature, no authorization. Don't start the work.
Contractor Signature: _________________________ Date: ________
Client Signature: _________________________ Date: ________
Both signatures, both dates. Hand it to them, get it back signed, then start the work.
The Homeowner Conversation: Script That Gets Signatures
This is the part contractors avoid because it feels awkward. Here's the exact script — adapt it to your voice, but don't skip it.
Opening:
"I want to make sure we're both clear on the additional work before I schedule it. The original scope didn't include running the line to the garage, so I need to put together a change order. It should take about five minutes — I just need your signature on the scope and the cost."
If they push back ("can't we just figure it out at the end?"):
"I hear you — but if we don't document the change now, it creates problems when we close out the project. This protects both of us. The work won't start until we've both signed off on the scope and the cost."
If they're resistant to signing:
"I totally understand if you want to look it over — I can email it to you right now and we can do a quick call to go over it. The important thing is that we both agree on what the work includes and what it costs before I schedule it."
The key move: Send it by email. Even if they don't sign right then, an email approval ("sounds good, go ahead") is legally defensible and creates a paper trail. Follow up with a text: "Just sent the change order — let me know if you have questions."
The free template covers most jobs. But the Contractor Pack includes change orders plus contracts, invoices, lien waivers, and subcontractor agreements — everything you need when you're running a real business with real clients.
Start free — get the Change Order Form → Get the Contractor Pack →What to Do When the Client Won't Sign
This happens. Some clients resist paperwork even when it's clearly in their interest.
Step 1: Email with explicit approval request
Send the change order as an attachment. Write in the body:
"Per our conversation today: adding the garage circuit run as discussed. Here's the change order. Please reply with approval if you'd like me to proceed."
A client reply of "approved" or "looks good, proceed" creates a written record that a court will recognize as acceptance.
Step 2: Text follow-up with summary
After the email, send a text:
"Just sent the CO for the garage circuit. Once you approve I'll schedule the work for [date]. Let me know if you have questions."
This creates a second thread with a timestamp. If they say "yes do it" via text, you've got written authorization.
Step 3: If they ghost or refuse
Do not start the work until you have written authorization. If the client won't sign or approve by email, the safest call is to not proceed. Walk the line politely: "I'd love to do this work — just need the change order signed so we're both protected."
The worst outcome is doing $2,000 of work and having the client dispute whether it was authorized. You don't want to be right and unpaid. Get the signature first.
Quick Reference: Change Order Checklist
Before you hand any change order to a client:
- Change order number assigned (sequential from original contract)
- Description is specific — no vague language, no general "additional work"
- Cost breakdown shows labor × rate and materials separately
- Schedule impact written (even if "0 additional days")
- Revised contract total calculated and shown
- Payment terms for this change order specified
- Your signature and date filled in before handing it over
- Client signature obtained before work begins
- If client won't sign: email approval request sent and replied to
Related Resources
- Contractor Payment Terms Template — how to write payment terms into your contract so change orders actually get paid
- Free Change Order Template — the filled-in example with all 8 fields
- HVAC Contractor Templates — change orders and contracts for HVAC professionals
- Plumbing Contractor Templates — field-ready change order forms for plumbers
- Roofing Contractor Templates — scope documentation and change order forms for roofers