A change order is a written agreement that modifies your construction contract’s scope, cost, or timeline after it is signed. They happen when you request a change or the crew uncovers a hidden problem. Change orders typically add markup on top of direct costs, often 15% to 25% on residential work. The golden rule is simple: never let work proceed without a signed change order.
Key Takeaways
- A change order is a written, signed modification to your contract’s scope, cost, or timeline, and it becomes part of the original agreement.
- Change orders are normal. On many projects they account for 10% to 15% of total contract value, and sometimes more.
- They are usually priced as direct costs (labor, materials, equipment) plus a markup, commonly 15% to 25% on residential work.
- The golden rule: never allow work to proceed on a verbal “yes.” Get every change in writing and signed before it happens.
- Most change orders come from owner-requested upgrades, unforeseen conditions found during demolition, or gaps in the original plans.
- A detailed scope and early material selections are the best defense, since vague plans invite scope creep and repeated changes.
Table of Contents
- What a Change Order Actually Is
- Why Change Orders Happen
- How Change Orders Are Priced
- The Golden Rule: Everything in Writing
- Lump Sum vs Time and Materials Changes
- How to Minimize Change Orders
- Change Order Red Flags
- Frequently Asked Questions
- Final Word
What a Change Order Actually Is
A change order is a written agreement that modifies a construction contract after it has been signed. It formally adjusts the scope of work, the price, the timeline, or all three, and once both parties sign it, it becomes part of the original contract. In short, a contractor change order is the official mechanism for changing the deal when something about the project shifts mid-stream.
This matters because your original contract is a fixed agreement for a defined scope at a defined price. The moment anything departs from that scope, the contract needs updating to reflect the new reality. That is true whether you ask for an upgrade or the crew finds a problem. A change order does exactly that. Without one, you have work happening that no signed document covers, which is where disputes are born.
Change orders are a completely normal part of construction, not a sign that something has gone wrong. Industry data from sources like Angi shows they account for roughly 10% to 15% of total contract value on many projects, and more than a third of projects experience at least one significant change order. Expecting them, and knowing how to handle them, is part of being a prepared homeowner. This connects directly to the budgeting reality in our pillar on how much a general contractor costs.
Why Change Orders Happen
Change orders usually trace back to one of three sources, and understanding them helps you predict and prevent many. The first is owner-requested changes. Once a project is underway and you can see the space taking shape, it is natural to want a design change: an upgrade, an extra outlet, better tile, or a moved wall. Every one of those requests is a change to the agreed scope, and each becomes a change order.
The second source is unforeseen conditions, the surprises that hide behind walls and under floors. Demolition regularly reveals mold, rotted subfloor, outdated wiring that fails code, or plumbing that must be replaced. None of this was visible when the contractor bid the job, so fixing it falls outside the original scope and requires a change order. This is exactly why a contingency fund matters, a point our guide to the hidden costs of hiring a contractor covers in detail.
The third source is gaps or errors in the original plans. If the drawings were vague, missing details, or simply wrong, the work has to be corrected as it becomes clear, and that correction is a change order. Regulatory or code requirements that surface during permitting or inspection can trigger them too, adding both cost and a possible project delay. Left unmanaged, these are a leading cause of cost overruns. Notice the pattern: the vaguer the starting scope, the more change orders follow. That is why the detail in our guide on how to read a contractor estimate protects your budget so effectively.
How Change Orders Are Priced
Change order pricing works much like the original bid, as direct costs plus a markup. The direct costs break into labor, materials, equipment, and any subcontractor work the change requires. On top of that, the contractor adds a markup to cover overhead and profit, since the change consumes the same business resources as the base work. Reputable contractors itemize all of this on a standard form like the AIA G701, published by the American Institute of Architects, rather than handing you a single lump number.
A quick example shows the math. Say the crew finds rotted subfloor during a bathroom demo. The fix needs $900 in materials, $1,400 in labor, and $200 in equipment, for $2,500 in direct costs. At a 20% markup, the change order totals $3,000, and the contractor lists each line so you can see where the number comes from. Compare that to a change order that simply reads “subfloor repair, $3,000” with no breakdown. Same price, but only one of them lets you check the work. The itemized version is the mark of a professional.
The markup is where homeowners often have questions. On residential work, a markup of 15% to 25% on direct costs for combined overhead and profit is common, in line with HomeAdvisor cost guidance. A fair contractor applies the same markup they used in the original contract. Some also add a small administrative fee, often $50 to $250 or a small percentage, to cover the real time of stopping work, re-planning, and re-ordering. A contractor should not discount change-order markup as a favor, and you should not expect them to, because that markup covers real costs.
It also helps to understand why changes cost more than the same work would have in the original bid. A change interrupts an established workflow, may require crews to demobilize and remobilize, and carries administrative and scheduling ripple effects. That is why adding a feature mid-project almost always costs more than it would have if it were in the plans from day one. Understanding markup here ties directly to our guide on contractor markup.
The Golden Rule| Everything in Writing
If you remember one thing about change orders, make it this: never allow work to proceed on a verbal agreement. A casual “sure, can you add two outlets while you’re here?” feels harmless, but without a signed change order it becomes a dispute waiting to happen. When the final invoice arrives with charges you do not remember approving, neither side has proof of what was agreed, and the relationship sours fast.
A proper change order should be a real document, not a handshake. It should describe the change in specific detail and break the cost into labor, materials, and markup. It should also state any impact on the timeline, show the new revised contract total, and carry dated sign-off from both you and the contractor. That written approval is what protects everyone. That paper trail protects both sides. It proves what you approved and what it costs, and it keeps the running total of your project honest as changes accumulate.
Insist on approving each change order before the work happens, not at the end of the project. Real-time approval prevents sticker shock and lets you decide whether an upgrade is worth it while you still have a choice. A contractor who wants to “keep a running list and settle up later” is creating exactly the ambiguity you want to avoid. This discipline pairs naturally with tying payments to progress in our contractor payment schedule guide. It also works with the warning signs in our red flags when hiring a contractor guide.
Lump Sum vs Time and Materials Changes
Change orders are generally priced one of two ways, and knowing the difference helps you evaluate them. A lump sum change order sets a single fixed price for a clearly defined change. If you decide to add six recessed lights and the scope is obvious, the contractor can quote one firm number. This gives you cost certainty upfront, which is ideal when the work is well understood.
A time and materials change order is used when the scope is hard to pin down in advance. The contractor bills for the actual labor hours, material costs, and equipment used, plus an agreed markup. This suits situations like uncovering hidden damage, where no one can know the full extent until the work is opened up. The trade-off is less certainty, so it is smart to ask for a not-to-exceed cap that limits your exposure if the work runs long.
Which method fits depends on the change. Well-defined upgrades belong in lump sum change orders, while truly unknown repairs often have to run on time and materials. This mirrors the broader cost-plus vs fixed price contract choice, which our guide on cost-plus vs fixed-price contracts explains in full. Either way, the pricing method should be stated in the change order so there is no confusion about how the final number was reached. If a price seems off, you can negotiate the labor hours or markup before you sign, which is part of a healthy change order process.
How to Minimize Change Orders
You cannot eliminate change orders, but you can dramatically reduce them with preparation. The single biggest lever is a detailed, complete scope of work before construction starts. When the plans specify materials by brand and grade, define every element of the work, and leave little to interpretation, there are far fewer gaps for changes to fill. Time spent getting the plans right upfront saves multiples in avoided changes later. A good contractor helps here, walking you through decisions during planning rather than during demolition. If your contractor rushed the estimate and left big pieces vague, expect more changes and more cost. Thorough pre-construction planning is not glamorous, but it is the cheapest insurance against a budget that balloons one change order at a time.
Make your major material selections early, before the job begins. Allowances left open become change orders the moment your real choice differs from the placeholder. Choosing cabinets, countertops, flooring, and fixtures ahead of time turns those placeholders into firm prices. In fact, allowance adjustments are technically change orders themselves, which is one more reason our guide to what a contractor allowance is stresses deciding early.
Finally, guard against scope creep, the slow accumulation of small “while you’re at it” requests that quietly balloon a budget. Each little addition seems minor, but twenty of them across a project add up to real money and time. Keep a clear list of what is in scope, run any new idea through a quick cost check before approving it, and be honest with yourself about must-haves versus nice-to-haves. Budgeting a contingency of 15% for the surprises you cannot prevent rounds out the strategy.
Change Order Red Flags
Most change orders are legitimate, but a few patterns should put you on alert. The first is any push to do change work without written documentation. A contractor who says “we’ll just add it to the bill” or resists putting a change in writing is creating ambiguity that rarely works in your favor. Insist on a signed change order every time, no exceptions.
Watch for pricing that lacks a breakdown. A change order that shows a single lump number with no itemized labor, materials, and markup deserves questions, since transparency is exactly what protects you. Be cautious too of a contractor whose original bid came in suspiciously low and then generates a stream of change orders. That can be a tactic to win the job cheap and recover margin later. This is one reason comparing bids on completeness matters, as our guide on why contractor bids are so different explains.
Finally, be wary of vague contract language around changes. Your original contract should spell out the change-order process, including how changes are documented, how they are priced, and what markup applies. If that language is missing or hazy, clarify it before you sign, not after a dispute erupts. A contractor who handles change orders with clear documentation and fair, consistent pricing is showing you exactly the professionalism you want for the whole project.
Frequently Asked Questions
What is a change order in construction?
A change order is a written agreement that modifies a construction contract’s scope, cost, or timeline after it has been signed. Once both parties sign it, it becomes part of the original contract. Change orders happen when you request a change or the crew uncovers a problem that falls outside the agreed scope, and they formally document the new work and its cost.
How much do change orders cost?
A change order is priced as direct costs (labor, materials, and equipment) plus a markup for overhead and profit, commonly 15% to 25% on residential work. Some contractors add a small administrative fee of $50 to $250. Changes usually cost more than the same work in the original bid because they interrupt the workflow and add scheduling and administrative burden.
Who pays for a change order?
The homeowner typically pays for change orders, since they add scope or cost beyond the original contract. The exception is when a change corrects an error the contractor made or work they failed to include that was clearly in scope. That is why documenting every change in writing matters: it clarifies what was agreed and who is responsible for each added cost.
Are change orders normal?
Yes, change orders are a completely normal part of construction. Industry data shows they account for roughly 10% to 15% of total contract value on many projects, and over a third of projects see at least one significant change. They are not a sign something went wrong. What matters is that each one is documented, priced fairly, and approved in writing before the work happens.
How do you avoid change orders?
You cannot eliminate them, but you can reduce them sharply. Start with a detailed, complete scope of work, specify materials by brand and grade, and make major selections before construction begins so allowances become firm prices. Guard against scope creep by running new ideas through a cost check first. Then budget a 15% contingency for the surprises you cannot prevent.
What should be included in a change order?
A proper change order should describe the change in specific detail, break the cost into labor, materials, equipment, and markup, state any impact on the timeline, show the new revised contract total, and include dated signatures from both the homeowner and the contractor. This itemized, signed document protects both sides and keeps the running project total accurate as changes accumulate.
Final Word
Change orders explained simply: they are the written, signed agreements that update your contract when the scope, cost, or timeline changes. They are normal, expected, and manageable, often running 10% to 15% of a project’s value. They are priced as direct costs plus a markup, usually 15% to 25% on residential work. They cost more than the same work would have in the original bid because changes disrupt an established workflow.
The way to stay in control is discipline. Never let work proceed on a verbal yes, insist on an itemized and signed change order for every modification, and approve each one before the work happens. Reduce them at the source with a detailed scope and early material selections, guard against scope creep, and keep a 15% contingency for the surprises you cannot avoid. Handle change orders this way and they become a normal part of a well-run project rather than a source of conflict. That discipline keeps your answer to how much does a general contractor cost close to the plan. For the complete cost picture, return to our pillar on how much a general contractor costs.
