Change Order Calculator
Price every change order properly and send a professional document — no more handshake deals that cost you money.
What is the Change Order / Scope Creep Cost Calculator?
The Change Order Calculator prices mid-job scope changes properly — new materials, added labor, schedule impact, and margin — so contractors capture the true cost of ‘while you’re here’ requests instead of absorbing them as free work.
How is it calculated?
Enter the added materials, extra labor hours at your loaded rate, any schedule-delay cost, and your standard margin. The calculator produces a documented change-order price and shows what absorbing the change silently would cost you.
Worked example: what should you charge for extra framing and drywall on a $15,000 job?
- Price the labor
The client wants extra framing and drywall. It’s 12 added hours at your $45/hr rate: 12 hrs × $45 = $540 in labor.
- Add materials to get base cost
Add the $800 in extra materials to the labor: $800 + $540 = $1,340. That’s your raw cost before any profit.
- Apply your markup
Run your 20% markup on the base cost: $1,340 × 20% = $268. That’s the profit you’d otherwise eat if you did this as a handshake favor.
- Get the change order total
Add markup back to base: $1,340 + $268 = $1,608. This is the amount you invoice for the change, on top of the original bid.
- Update the contract total
Original bid plus the change order: $15,000 + $1,608 = $16,608 is the new job value.
- Takeaway
A quick ‘sure, I’ll throw it in’ would have cost you $268 in profit and $1,340 in unbilled cost. Send the $1,608 change order and get it signed before you pick up a hammer.
What does each markup rate do to a $1,340 change order?
| Markup % | Markup earned | Change order total | New contract total |
|---|---|---|---|
| 0% (favor) | $0 | $1,340 | $16,340 |
| 10% | $134 | $1,474 | $16,474 |
| 15% | $201 | $1,541 | $16,541 |
| 20% (default) | $268 | $1,608 | $16,608 |
| 25% | $335 | $1,675 | $16,675 |
| 35% | $469 | $1,809 | $16,809 |
Frequently Asked Questions
How should contractors price a change order?
Price it like a small job: added materials with waste, labor at fully burdened rates, any remobilization or schedule cost, plus your standard margin — many contractors also add a 10–15% administrative fee. The one thing never to do is price it at bare cost to ‘keep the client happy.’
Why do change orders destroy contractor profit?
Because they’re often verbal, unpriced, and absorbed. Industry studies put change-order work at 8–14% of contract value on typical jobs; absorbing even half of that on a 20%-margin business erases a quarter of the profit. Documentation, not generosity, is the fix.
Should small changes be free to maintain goodwill?
Set a written threshold — say $250 — below which changes are included, and price everything above it. This preserves goodwill on trivial requests while training the client that scope has a price. Unlimited free changes teach the opposite lesson.
What must a change order document include?
Scope description, itemized price, schedule impact in days, payment terms, and the client’s signature before work proceeds. A signed change order converts a dispute risk into billable revenue and is enforceable where a verbal ‘go ahead’ is not.
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