If you do extra work without a signed change order, you are gambling on getting paid for it, and you will often lose. A change order is a short written record that says: here is the extra work, here is what it costs, here is the new finish date, signed by both of you, before the work starts. Get one every single time the job changes, and "can you just also do X while you're here" stops being a fight at the end.
Why a verbal yes does not hold up
Extra work is where most payment disputes begin. The customer asks for one more thing, you say sure, you do it, and at the end there is an argument about whether it was always included in the price. You remember a favor. They remember it as part of the job. You have nothing in writing, so you eat it. Multiply that across a job and the "extras" you never charged for are your whole profit, gone.
What a change order needs
It does not have to be fancy. It has to have:
- The extra work, described plainly.
- The price for it, and whether it is a fixed amount or time and materials.
- The schedule impact, even if it is "no change."
- Both signatures and the date, before the work is done.
That is it. The power is in the "before," not the paperwork.
The discipline that makes it work
- Put a clause in your contract that says extra work needs a signed change order, then actually enforce it.
- When the customer is standing right there wanting it now, pause and write the change order anyway. The two minutes it takes is nothing against the two-month payment fight it prevents.
- If you already did the extra work on a handshake, it is harder to collect, but still write it up and bill it. And treat it as the lesson for next time.
- Settle the rate before the change, not during it. If extras are going on time and materials, get the hourly rate and the materials markup into the original contract, so that when a change comes there is nothing left to argue about except the hours. The contract that protects you covers the clause that does it.
- If it has already gone wrong and the money is outstanding, Not been paid? Here's your ladder of options. is the next step, and How to write a demand letter that actually gets you paid is the first rung of it.
The Change Order Form does the whole thing in about a minute on your phone, so there is no excuse to skip it.
When they will not sign
This is the moment the rest of it is actually for. You have written the change order, the customer is standing in front of you, and they will not put their name to it. You have three moves, and it is worth knowing which one you are choosing rather than drifting into one.
- Stop at the edge of the original scope, and say why. The strongest move and the one people are most afraid of. You are not downing tools on the job, you are declining to do work nobody has agreed to pay for. Say it plainly, then put it in writing the same day: what was asked for, what it costs, what it does to the finish date, and that you are ready to start the moment it is signed. Most of the time the signature arrives.
- Proceed under written protest. Sometimes stopping costs you more than the extra is worth, or the sequence genuinely cannot pause. Then do the work, but send an email BEFORE you start it saying what you were directed to do, that you consider it outside the contract, what you expect it to cost, and that you are proceeding to keep the job moving without giving up your claim for it. An email they never replied to is far better evidence than a conversation neither of you remembers the same way. That written record is the same evidence a constructive-change claim needs, and the FAQ below sets out what such a claim has to prove.
- Absorb it, on purpose. Sometimes eating a small extra to keep a good customer is the right call. That is a business decision and there is nothing wrong with it. What sinks contractors is absorbing extras by accident, one at a time, never having decided to.
The fourth option is the one to avoid: do the work, say nothing, and put it on the final invoice. That is the version that turns into a fight at the end of the job, and it is the fight you are most likely to lose, because by then the only person with a written record of the extra is nobody.
Common questions
Can I charge for extra work without a signed change order?
You can try, but you are gambling. Without a signed change order you carry the full burden of proving the extra work existed, that it was authorized, and what it was worth. If your contract has a no-oral-modifications clause, an unsigned change can be unenforceable outright. Some states let you recover under unjust enrichment when the customer clearly knew about and accepted the work, but many do not, and it is a hard, expensive argument. Write the change order before the work every time.
What is a constructive change order?
A constructive change is when the customer's action or inaction changes your scope without anyone issuing formal paperwork, like conflicting drawings, site conditions, or a directive to speed up. To get paid for it you have to prove four things: someone with authority directed the change, you actually deviated from the original contract, you are entitled to more money or time, and you gave timely notice. Document it in real time with photos and written confirmation, because the proof is on you.
Do change orders have to be signed before the work starts?
Best practice, and what standard contract forms require, is a change order signed by both parties before the extra work begins. The power of a change order is in the timing, not the paperwork. Signed up front, there is no dispute later about whether it was included or what it costs. Done after the fact, you are back to arguing, so pause and write it even when the customer wants it done right now.
How much can I mark up a change order?
Markup on change-order work is negotiated, not fixed by law, and the smart move is to lock a stated overhead-and-profit percentage into your original contract so there is nothing to argue about when changes come up. Standard-form contracts let you propose a markup, and a stated percentage in the original agreement removes the fight. Set it once, apply it to every change, and price the extra as either a fixed amount or time and materials with a cap.
The honest bit
- On commercial jobs, the contract usually dictates the exact change-order process, including notice deadlines for claiming extra time or money. Follow it to the letter, because missing a notice deadline can kill an otherwise valid claim.
- This is general guidance, not legal advice.
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