How to Write a Change Order That Gets Signed (and Paid)

It starts with "while you're here, could you also…" and ends with a final invoice the customer doesn't want to pay. Unwritten changes are one of the biggest profit leaks in contracting. The fix is simple and boring: a written, signed change order every single time the scope, price or schedule changes.

When you need a change order

• The customer adds or removes work.
• The customer changes a selection (fixtures, finishes, materials).
• You uncover a hidden condition: rot, bad wiring, an undersized beam, anything your contract says is extra.
• The inspector or code requires something the original scope didn't include.
• A customer-caused delay changes your schedule or costs.

If it changes what you're doing, what it costs, or when you'll finish, write it down before you do the work.

What every change order needs

1. Reference to the original contract: project address, contract date, and a change order number (CO #1, CO #2…).
2. A clear description of the change. Specific enough that a stranger could tell what's included: "Replace 14 lf of rotted rim joist at rear wall with new PT 2x10, including removal and disposal" beats "fix floor."
3. The reason: customer request, hidden condition, or code requirement. This matters later if there's a dispute.
4. The price: labor, materials, and your markup, shown as an add or a credit, plus the new contract total.
5. Schedule impact: how many days it adds, even if the answer is zero.
6. Payment terms: due now, with the next draw, or at completion.
7. Signatures and dates from both sides, before the work starts.

Five habits that get change orders signed fast

1. Set it up in the original contract. Your contract should say that changes require a written change order and that hidden conditions are billed as extra. Then a change order isn't a surprise, it's the process the customer already agreed to.

2. Write it on the spot. The best time to get a signature is the moment the customer asks for the change, while they're excited about it. A fillable form on your phone or tablet makes this a two-minute job.

3. Show photos for hidden conditions. A picture of the rotted joist or the melted wire ends the argument before it starts.

4. Give the price, not a range. "About a thousand, maybe more" invites a fight. If you can't price it yet, write a not-to-exceed number or do it on time and materials, and say so in writing.

5. Don't start until it's signed. This is the hard one. If the customer won't sign, they won't pay. Pause that piece of work and keep going on the rest.

Make sure it gets paid

Add each approved change order to your running contract total and bill it on the next invoice or progress draw as its own line item. On bigger jobs, a schedule of values with a separate change-order line keeps everything visible, so the final bill is never a shock. When the last payment comes in, a lien waiver for that payment keeps lenders and owners happy.

A quick example

CO #2 — 214 Elm St. — Kitchen Remodel (contract dated March 3)
Description: Customer requested upgrade from standard to under-cabinet LED lighting, 4 runs, including dimmer and wiring.
Reason: Customer request.
Price: Add $1,140. New contract total: $48,640.
Schedule: Adds 1 day.
Payment: Billed with next progress draw.
Signed: Customer / Contractor, with dates.

Doing bigger jobs? The Progress Billing & Schedule of Values tracks approved change orders on every draw, and the Contractor Business Bundle includes the change order form, sub agreement, lien waivers and 14 more templates.

This article is general information, not legal advice. Contract and notice requirements vary by state, so have a local attorney review your contract documents.