What Is a Change Order? Explained

A change order is a written amendment or change to your contract. It records any change to the agreed scope of work after the contract is signed, along with what that change does to the price and the schedule.

Your contract describes a specific job at a specific price. Once work starts, things shift: you decide to add something, the contractor opens a wall and finds a problem, or an inspector asks for something no one planned. A change order is how that shift gets written down and agreed to by both of you, so the contract always matches the job actually being built.

A change order can add cost, reduce cost (if you remove something from the scope), or change only the schedule. What makes it a change order isn't the direction of the money. It's that the original agreement is changing.

Yes, change orders are normal. Nearly every renovation has some. The warning sign isn't the number. It's where they come from and how they're handled.

A handful of change orders on a kitchen or bathroom, most of them because the homeowner added something or a hidden condition turned up, is an ordinary project. A pattern is what's concerning:

• Change orders for work that was already included
• Change orders with no paperwork, or that show up only after the work is done
• Vague descriptions with a single dollar figure and no explanation
• Every question treated as a change order

For other warning signs, see Contractor Red Flags, Explained.

Most change orders fall into one of four types, and the type usually decides who should pay.

• Homeowner changes. "Can we add a light here?" "I changed my mind on the tile." The homeowner asked for it, so the homeowner pays.
• Unforeseen conditions. Rot, outdated wiring, or plumbing hidden in a wall, found after demolition. If no one could reasonably have seen it, it's usually the homeowner's cost. That's what contingency is for.
• Scope or design gaps. Something was never defined clearly enough to price. Who pays depends on who wrote the scope and what the contract says. It's often negotiated.
• Errors or omissions. The work was already in the scope, or someone made a mistake. This is generally not the homeowner's cost.

Usually, yes. When your actual selection costs more than the allowance in your contract, the difference is typically billed as a change order, and coming in under it should give you a credit.

How allowances work, and how to tell if yours are realistic, is covered in What Is a Renovation Allowance? Explained.

A proper change order spells out what changed, why, what it costs, and how it affects the schedule, and it's signed by both parties before the work starts.

A complete change order should include:

• A description of the change, compared with the original scope
• The reason for the change
• The cost of the change, including any fees or markup
• The effect on the schedule, even if the answer is "none"
• Any new drawings, permits, or inspections required
• When payment is due
• The date, a change order number, and both signatures

The number matters more than it seems. A running sequence (CO #1, CO #2, CO #3) is what makes it possible to see what's been approved and to spot a charge that appears twice.

Yes. Markup on change orders is standard: the contractor is coordinating the added work, carrying the risk, and often reshuffling the schedule. There's no single normal number, because companies structure it very differently.

Structures you'll see include:

• Separate line items, for example 10% markup, 10% for liability, and 5% for insurance
• A flat percentage on any change order, sometimes 30% or more
• Actual time and materials, plus a percentage markup
• A flat fee per change order, with no markup broken out

None of these is wrong on its own. What makes markup fair is that the method is written into the contract before any change order appears, and applied the same way every time.

You should, and a well-written contract requires it. Written approval before the work begins is the strongest protection for both the homeowner and the contractor.

A standard change order clause says no change to the scope or price without a written change order, signed by both parties, before the work is done. For example, Massachusetts's sample contract language for home improvement work puts it simply: any change to the original contract "must be in writing and agreed to by both parties."

The clause protects the contractor too. It keeps them from doing work they believed was approved and then finding out it wasn't. When both sides sign first, there's nothing to argue about later.

It can. A text or email can be evidence that you agreed to a change, and in some situations even a verbal yes can create an obligation to pay. No signature doesn't automatically mean no bill.

This is where many disputes start. A homeowner says "sure, go ahead" on site, the work gets done, and the price shows up later. Whether the homeowner owes it depends on the contract and state law, but "I never signed anything" isn't a reliable defense, especially when the homeowner asked for the work or watched it happen.

It also cuts the other way. A casual yes can commit you to something you didn't fully understand, at a price you never saw. That's the reason written, signed change orders exist.

They can bill for it, and sometimes the charge is legitimate. But if the contract requires written approval first and that step was skipped, the charge is on much weaker footing.

A common version: the project wraps up, and the final invoice includes thousands of dollars in extras that were never agreed in writing, sometimes including work the homeowner says they declined.

Whether it's owed usually comes down to three things: whether the homeowner asked for the work, what the contract says about approving changes, and state law. Work the homeowner requested may still be fair to pay for. Work that was never approved, under a contract that requires written approval, is a very different situation.

Hidden conditions are real, and paying for them is usually the homeowner's responsibility. A legitimate one is something no one could reasonably have seen or predicted before the work began.

Older houses hide things: rotted subfloor, outdated wiring, a drain line in the wrong place. When something like this turns up after demolition, a change order is fair, and a 10 to 20% contingency fund exists for exactly this. Contractors price a job based on what they've seen on hundreds of similar projects, and what's behind the wall is usually exactly what they expected. They don't have x-ray vision. When it's the one time in a hundred that it isn't, that usually isn't the contractor's fault.

What separates a real unforeseen condition from a questionable one is whether it was truly hidden. A contractor should be able to show you the condition and explain why it wasn't visible before the work started. Many contracts also include a hidden-conditions clause that sets out how these are priced.

If it was a genuine miss by the contractor, the contractor should generally cover it. If the scope was never clearly defined, the answer is less clear-cut.

It comes down to what the scope of work, the drawings, and the quote actually say. If the item is already there, it's included, and a change order for it asks the homeowner to pay twice. If the contractor priced the job and should reasonably have included something to deliver what was agreed, that's their omission.

It gets harder when the scope was vague. Homeowners often assume something is included because it makes sense to them, while a contractor prices only what's written down. A baseboard heater cover in a bathroom refresh is a common example: the homeowner expects a new one, and it was never in the scope. In cases like that, it's often nobody's fault, and it usually comes down to a good-faith conversation between the two of you. What a clear scope of work looks like is covered in How Do I Get Accurate Contractor Quotes for a Renovation? Explained.

Code compliance isn't an upgrade. If the contractor's own work was required to meet code and didn't, fixing it is generally the contractor's cost, not a change order. But some inspector-driven work is a legitimate added cost.

A contractor is expected to know the code that applies to the work they're doing, and in most states, correcting defective work is the contractor's responsibility.

Inspector-driven work can be a fair added cost when it comes from:

• An existing condition in the home that wasn't part of the job
• A code upgrade the renovation triggered that no one could reasonably have anticipated
• A change the homeowner requested
• A design by an architect or designer that the contractor built as drawn
• An unusually strict or unexpected call by the inspector

When the requirement comes from an existing condition, or from a code upgrade the renovation itself triggered, the cost is generally the homeowner's. "It'll be grandfathered in" is a common assumption that doesn't always hold. Homeowners can question an inspector's decision or appeal it through the local building department, but that takes time, and the project usually waits while it's resolved.

Usually by accident. On a long project with many change orders, work that was already covered can show up again under a new description, and without a running record, neither side notices.

Duplicates tend to happen when:

• The same item is described differently on two change orders
• A later change order bundles work that an earlier one partly covered
• Something already in the original scope gets written up as an extra
• Change orders aren't numbered, so there's no easy way to compare them

A cabinet adjustment or floor leveling, for example, can end up billed once in the contract and again on a change order months later. A numbered change order log with a running total is what catches these.

Many change orders add time, not just money, and the delay is often bigger than the work itself. That's why every change order should state its schedule impact, even if that's "none."

Adding two recessed lights might take an hour. But if the electrician has already finished and has to come back, or drywall has to wait for another inspection, that hour can turn into days. A tile change can mean weeks waiting for new material. Moving a fixture can mean revised drawings or a permit amendment.

The schedule cost ripples forward, because every trade after the change has to shift too. Sometimes that, not the price, is the real cost of a small change.

Typically when it's approved, before the added work starts. Some contractors add it to the next scheduled payment, but that's less common.

Most contractors want change orders paid up front. The payment is their green light to order materials and schedule the work, and it keeps added costs from piling up into a surprise at the end. Either way, the payment timing should be written on the change order itself.

Change orders shouldn't change the rest of the payment schedule. If your contract ties the final payment to completion of the punch list, that still holds. How deposits, progress payments, and the final payment should work is covered in How Do Contractor Payment Schedules Work? Explained.

Yes. Any change order can be negotiated, and any change the homeowner asked for but no longer wants can be declined. Work required to finish the job safely or legally is harder to refuse, but the price and approach are still open to discussion.

For optional work, "no" is always an answer, and so is "not now." A change can be scaled down, swapped for a lower-cost alternative, or done separately after the project.

For required work, like a hidden structural problem or a code requirement, declining usually isn't realistic, because the job can't be finished without it. How it's priced, and whether there's more than one way to fix it, are still fair questions.

Possibly. Depending on the contract and state law, a contractor may be able to stop work over nonpayment, and unpaid contractors, subcontractors, and suppliers may have lien rights against the property.

A lien is a legal claim against your property for unpaid work or materials. Lien rules vary a lot by state, including deadlines and notice requirements, and in some states subcontractors and suppliers can file one even if the homeowner paid the general contractor

That's why homeowners in a dispute generally stay on firmer ground by continuing to pay the undisputed parts of the contract and disputing the specific change order in writing, rather than withholding everything. For larger amounts, a construction attorney or the state consumer protection office is the right next call.

Most avoidable change orders come from decisions made late or never written down.

The most common causes:

• A vague scope of work, so each side assumed something different
• Selections (cabinets, tile, fixtures) made after construction started
• Allowances set too low for the finish level the homeowner actually wanted
• Small "while you're here" requests that never got written up

That last one matters more than it sounds. An extra outlet, a little more tile, moving a switch: each feels too small to write up. Together, they're how projects end with thousands of dollars in extras and two people remembering things differently.