Contractor change orders: what to include, how to price them, and how to get signed and paid

Almost every job changes. The homeowner sees the new cabinets go in and wants the pantry to match. The tear-off shows soft decking nobody could see from the ground. The new air handler will not fit the old return without a rebuilt plenum. None of that is unusual. What turns it into lost money is handling it with a conversation in the driveway and a promise to sort it out on the final invoice.

By then, memories have drifted. The homeowner remembers a smaller number. Without a signed piece of paper you are negotiating from nothing, and the easy way out is to eat part of the cost. A clean change order process fixes that: a habit, a template and a rule about timing.

What a change order must include

One page is plenty for most residential changes. It just needs to be specific enough that a stranger could read it and know exactly what was agreed.

California spells most of this out. Its home improvement contract law says a change order must describe the scope of the extra work, the cost added to or subtracted from the contract, and the effect on the progress payments or the completion date, and that it becomes part of the contract only if it is in writing and signed before the work starts (California Business and Professions Code section 7159). Oregon's Construction Contractors Board publishes a sample change order with the same basic shape: the original contract date, the changes, a new completion date, the original and revised contract price, and signature lines for both parties.

When you need a change order

The simple rule: if anything in the signed contract is about to change, write it down first. That covers more than homeowner upgrades. Use a change order for any of these:

• The homeowner asks for more. An extra outlet, a different tile, a bigger window, another room painted.
• You find a hidden condition. Rotted decking, water damage behind a wall, failed ductwork, framing that is not what the drawings showed.
• Code or the inspector requires something new. A required upgrade that was not in the original scope.
• A material changes. The specified product is discontinued or back-ordered and a substitute costs more or less.
• Scope comes out. The homeowner drops part of the job. A credit change order keeps the contract total honest and protects you from a later claim that the price should have dropped more.

How to price a change order

Many contractors price a change at cost plus a little, because charging full margin mid-job feels awkward. That is backwards. Change work usually costs more to do than planned work: the crew stops and rearranges, and the office spends time on scope and paperwork.

1. 1

   Build the direct cost

   Materials at your actual cost, including delivery, plus labor hours at your loaded labor rate. If you do not know your loaded rate, work it out once with the job cost and hourly rate calculator.

2. 2

   Add the cost of the disruption

   Remobilization, extra supervision, a return trip, a permit revision, dumpster time. These are real costs that only exist because of the change. List them.

3. 3

   Apply your normal markup

   Use the same markup you use on the base job, so the change earns the same gross margin. Remember that markup and margin are different numbers: a 50 percent markup is a 33 percent margin. Check it with the markup and margin calculator.

4. 4

   Price credits honestly

   When scope comes out, credit the direct cost you save, not the full sell price, and state that policy in the original contract.

A worked example

Here is an illustrative example, not a market price. Midway through a kitchen remodel, the homeowner asks for four more recessed lights and a dimmer before the ceiling is closed.

If this contractor had billed the change at cost plus 10 percent, the price would have been $1,342. The job gets bigger and the margin on the whole job gets smaller, which is how busy remodelers end up working harder for less.

Get the signature before the work

The rule that matters most is timing. Sign first, then build. In California it is not just good practice: a change order becomes part of the contract only if it is in writing and signed by both parties before any of the covered work begins, and California's contractor board tells consumers the same thing (CSLB). Other states handle it differently, so check yours, but signing first protects you everywhere.

Crews skip it because of friction: the homeowner is at work and the crew is on the roof. An electronic signature removes most of that. Under federal law, a contract or signature in interstate commerce cannot be denied legal effect solely because it is electronic (15 U.S.C. 7001), though your state may have its own rules for certain documents.

1. 1

   Stop and photograph

   Before touching the new work, photograph the condition or area. For hidden damage, shoot it wide for context and close up for detail. Our guide to photo documentation covers what to capture.

2. 2

   Call or text the homeowner

   Explain what you found in plain language before any paperwork arrives. A change order with no warning feels like an ambush.

3. 3

   Send the written change order

   Description, price, new total, payment terms, schedule effect and photos, sent to their phone for signature.

4. 4

   Wait for the signature

   No signature, no work on that item. Keep the crew busy elsewhere on the job while you wait.

5. 5

   File it on the job

   Keep the signed change order and photos on the job record, so the office bills it.

When change orders get paid

Most change order fights are not about the amount. They are about when it is due. Pick a rule, put it in your original contract, and repeat it on every change order. Common options:

Whatever you choose, the change order should state it, which California's law already requires by asking for the effect on progress payments. If your state limits deposits on home improvement work, the same limits can matter for a change order paid in advance, so read our guide to deposits, draws and stage payments and the state statutes it links before you set your rule. When the job is done, approved change orders should already be on the final invoice, so you can collect the balance before you leave, as covered in how to get paid on the day of the job.

Handling change order disputes

Even with good paperwork, homeowners sometimes push back. How you respond decides whether you keep the relationship and the money.

• If it is signed, show it calmly. Pull up the signed change order and the photos. Most disputes end there, because the homeowner genuinely forgot the details.
• If it is not signed, own the gap. Explain what was done and why, show the photos, and offer a fair price. Expect to negotiate, and treat it as the cost of learning the habit.
• Separate the disputed amount from the rest. Collect the undisputed contract balance now and resolve the change separately, rather than letting one line hold up the whole invoice.
• Know your options before you need them. Your contract's dispute clause, your state licensing board and small claims court all have rules. Talk to an attorney before threatening a lien or legal action, since lien rules and deadlines vary by state.

Change order examples by trade

Remodeling: the upgrade and the surprise

Upgrades are the easy changes: a better faucet, tile to the ceiling, a heated floor. Price them from your catalog at your normal markup and collect for special-order items at signing if your state allows it. Surprises are harder: rotted subfloor under a toilet, or wiring that must come up to code once the wall is open. Name these risks in the original contract, and when you find one, stop, photograph and send the change order.

Roofing: wood rot under the shingles

Nobody sees the decking until the old roof is off, and by then the homeowner may be at work. Put a unit price for replacing damaged decking in the original contract, such as a price per sheet, and explain it during the presentation. When tear-off shows rot, the crew photographs it, counts the sheets, and the change order goes to the homeowner's phone at the agreed unit price, so the roof still gets dried in the same day. Even with a unit price in the contract, getting a signed change order is the safe habit.

HVAC: ductwork you could not see

On a system replacement, the surprises live in the ductwork: a return too small for the new system, a plenum that will not line up with the new air handler, crushed runs in the attic. Where you can, price likely duct work as a separate line on the original estimate. When something unplanned turns up on install day, photograph it, explain what happens if it is left alone, and send the change order before building the transition. Airflow problems left unfixed become callbacks.

Frequently asked questions

Further reading: California's contractor board explains change orders and contract requirements in its guide to home improvement contracts, and Oregon's board offers a sample change order form. For quoting the original job so fewer changes come up, see good, better, best pricing and Revcore estimates.