You finished the extra work. You got a signature on the change order before you touched a tool. Now the invoice is 40 days past due, and the owner is telling you they never agreed to any of it — and whoever signed your paper had no business signing anything. Suddenly that signature you were counting on is just ink on a page.
This is one of the quietest ways a contractor loses money. Knowing who signs a change order — and, more importantly, who has the authority to sign it — is the difference between a clean collection and a fight you might not win. A change order is only as good as the person who signs it. Get the wrong signature and you don't have an agreement. You have a problem.
Quick note: This is general information, not legal advice. Who can bind a party depends on your contract and your state. Confirm the specifics with your own attorney before you rely on them.
Why the wrong signature costs you the whole job
Here's the trap. On a jobsite, plenty of people act like they're in charge. The homeowner's spouse. The site superintendent. The office manager who emails you about everything. A tenant who wants the space changed. Any of them will happily wave you on and scribble a name when you show up with a change order.
The catch: waving you on and being legally able to commit the person who writes the checks are two very different things. If the signer can't bind the party who owes the money, that party can look at your signed change order and say, honestly, "I never authorized that." And in a lot of cases, they'd be right.
What that costs you is not small:
- Unpaid work. You've already spent the labor and materials. That money is gone whether or not you collect.
- A dispute you're set up to lose. When the paperwork doesn't tie back to the person responsible for payment, the burden shifts to you to prove they agreed.
- Slow pay or no pay. Even if you're eventually right, "eventually" can mean months of chasing, and sometimes a lien filing and everything that comes with it.
- A wrecked relationship. Nothing sours a good client faster than a surprise bill they feel they never approved.
All of it traces back to one avoidable question you didn't ask up front: does this person actually have the authority to sign?
Who signs a change order on a residential job
On residential work, the answer is usually simpler than people make it. The person who signs the change order should be the same person (or people) who signed the original contract. If both spouses are on the contract, get both on the change order, or at least confirm one is authorized to sign for the other. If only one name is on the contract, that's your signer.
Where builders get burned is assuming a household runs like a democracy. It doesn't — not legally. The spouse who wasn't on the contract, the adult kid who's "managing the project," the interior designer picking finishes: none of them can commit the homeowner to pay for a change unless the homeowner gave them that authority in writing. Verbal "yeah, go ahead" from a bystander is worth exactly nothing when the bill lands.
Who signs a change order on a commercial job
Commercial is where the authority question gets sharp, because the person on site is almost never the person with a checkbook. On a commercial project the change order should be signed by the owner or an owner's representative who is authorized to approve changes under the contract. That authority usually lives in the contract itself — who can approve changes, up to what dollar amount, and whether the architect or a project manager has to sign off first.
So before you take a signature from a "PM" or a "rep," read your contract and ask a blunt question: who is named as the party authorized to approve change orders, and is there a dollar limit on what they can approve without going higher? If a site super can green-light a $2,000 change but not a $40,000 one, you need to know that before you build the $40,000 one on their signature.
Who signs when you're a subcontractor
If you're a sub, your change order rides on your subcontract, and your signer is usually the general contractor — specifically whoever the GC has authorized to approve extras. The mistake subs make is taking direction from the owner or the owner's rep directly and skipping the GC. You might be doing exactly what the owner wants, but if your contract is with the GC, it's the GC's authorized signature that gets you paid. Owner said so? Great — get the GC to put it on a change order and sign it. We wrote a whole piece on the change order approval process if you want the full chain.
Grab the free Excel change order template
A professional, auto-calculating change order spreadsheet — line items, markup, tax and your revised contract value all worked out for you, plus a log to track every change order on the job. Free to download and use on any project.
Download the free Excel template →The people who can't bind the check
Keep a short mental list of folks who are easy to mistake for the decision-maker and usually aren't:
- A spouse or family member not on the contract — unless they have written authority to sign for the party who is.
- A tenant on a commercial fit-out, when your contract is with the landlord (or vice versa).
- A site superintendent or foreman without written approval authority, or over their dollar limit.
- An architect, designer, or consultant who influences the work but doesn't control the money.
- An owner's employee whose name isn't tied to change-order approval anywhere in the contract.
None of these people are lying to you when they say "do it." They genuinely think they can approve it. That's what makes it dangerous. Your job is to confirm authority, not to assume it based on how confident someone sounds.
How to prove the signer actually had authority
Getting the right person is half of it. Being able to prove you got the right person — months later, when memories have conveniently faded — is the other half. A few habits make this bulletproof:
- Establish authorized signers at contract signing. On day one, in writing, name who can approve change orders on the job and up to what amount. Now you're not guessing mid-project.
- Capture the signer's full name, title, and the date — every time. "Approved" with an illegible squiggle is not proof of anything. A name, a role, and a timestamp is.
- Put it in writing before the work, not after. A signature you collected after the work is done invites "I only signed because you already did it." Get it signed first.
- Keep the trail. Save the signed document, the email it came from, and the timestamp somewhere you can find it in ten seconds a year from now.
You can run this on paper if you're disciplined about it. The free Excel route is a solid start: our free Excel change order template gives you a clean signature block for a name, title and date, plus a running log so every signed change on the job sits in one place instead of scattered across a truck seat and an inbox.
Skip the Word doc. Send it in 30 seconds.
ChangeOrdersPro turns this into a 30-second job — fill in the change, hit send, and your client signs from their phone. The contract total updates itself. It’s 100% free.
Create a free change order →The reason the signature block matters so much is simple: when a payment fight starts, the first thing anyone asks is "who agreed to this, and when?" If your answer is a legible name, a title, and a date that lands before the work — you're in a strong spot. If your answer is a shrug, you're not.
Paper signatures vs. capturing identity automatically
Here's the honest weakness of paper and even a spreadsheet: they capture what someone wrote, not proof of who actually signed and when. A name typed into a cell can be typed by anyone. That's fine for your own records, but it's thin if things get contested.
The digital route closes that gap. When a change order is sent to a specific person and they sign it from their own phone, you get a record of the exact email it went to, the moment it was signed, and the signature attached to it — automatically, without you chasing anyone or reconstructing a timeline later. Same idea as the spreadsheet, but the "who and when" is captured for you instead of written in by hand. If you want that, the free digital change order tool does exactly this, and it costs nothing.
Neither approach is "better" for everyone. If you like a spreadsheet and you're careful, the template does the job. If you'd rather the proof capture itself so you never have to argue about a squiggle, the digital tool is built for that. Both are free, so it's genuinely down to how you like to work.
Frequently asked questions
Does it matter who signs a change order if the work still got done?
Yes. Doing the work doesn't guarantee payment — being able to show the person responsible for paying agreed to it does. A signature from someone without authority to bind the paying party can leave you holding the cost, even though the work is finished and correct.
Can a homeowner's spouse sign a change order?
Only safely if that spouse is on the original contract, or has written authority to sign for the spouse who is. If just one spouse signed the contract, that's the person whose signature protects you — don't assume the other can commit them without it.
Who signs a change order when I'm a subcontractor?
Usually the general contractor, or whoever the GC has authorized to approve extras. Even if the owner is the one asking for the change, your contract is with the GC, so it's the GC's authorized signature that gets you paid. Get the direction routed back through them.
Is a signature in the free Excel template enough to prove approval?
The free Excel template gives you a proper signature block (name, title, date) and a log, which is far better than a verbal okay. Just remember a typed name is only as strong as your records around it. If you want the who-and-when captured automatically, the free digital tool records the exact recipient and signing time for you. This is general information, not legal advice — confirm what your state and contract require.
Daisy writes about the unglamorous side of running a build — the paperwork, the change orders, and the conversations that keep a job profitable. ChangeOrdersPro is the free tool her team built so contractors can send a professional change order and get it signed from a phone in about 30 seconds.