Change Order Calculator

Calculate the full cost impact of construction change orders — labor, materials, overhead & profit.

Change Order Details

CO Number

Date

Change Order Title

Description of Scope Change

Cost Components

Labor Hours

Hourly Rate ($)

Material Cost ($)

Subcontractor Cost ($)

Equipment Cost ($)

Markup

Overhead %

Profit %

Status

Cost Breakdown

Labor Cost $0.00

Material Cost $0.00

Subcontractor Cost $0.00

Equipment Cost $0.00

Direct Cost Subtotal $0.00

Overhead (15%) $0.00

Subtotal + Overhead $0.00

Profit (10%) $0.00

Total Change Order Value $0.00

Overhead applied to direct costs. Profit applied to (direct costs + overhead).

Change Order Log

0 orders

CO #	Title	Status	Direct Cost	Overhead	Profit	Total
No change orders added yet. Use the Single Change Order tab to add COs.

Contract Values

Original Contract Value ($)

Change order totals are pulled automatically from your CO Log. Approved and pending COs are tracked separately.

Original Contract Value $0.00

Approved COs Total $0.00

Pending COs Total $0.00

Revised Contract Value $0.00

Change Order % of Original 0.00%

Contract Impact Chart

Pending COs are not included in revised contract value. Approved only.

How to Use This Calculator

Enter CO details — Fill in the change order number, title, and description in the Single Change Order tab. These fields are included in your CSV export.

Enter cost components — Add labor (hours × hourly rate), material costs, subcontractor costs, and equipment rental costs separately.

Set overhead & profit — Adjust the overhead percentage (default 15%) and profit percentage (default 10%). Overhead applies to direct costs; profit applies to direct costs + overhead.

Add to log — Click "Add to Log" to save the CO. View all COs in the Change Order Log tab with running totals.

Review contract impact — Enter your original contract value in the Contract Summary tab to see the revised contract total and percentage increase.

Key Formulas

Direct Cost Labor + Materials + Subs + Equipment

Overhead Amount Direct Cost × Overhead %

Profit Amount (Direct Cost + Overhead) × Profit %

Total CO Value Direct Cost + Overhead + Profit

Markup vs Margin Markup = Profit / Cost | Margin = Profit / Price

Revised Contract Original Value + Approved COs

Frequently Asked Questions

What is a construction change order?

A change order is a written amendment to a construction contract that modifies the original scope of work, price, or schedule. It is required whenever work is added, deleted, or altered after the contract is signed. Both parties must sign a change order before the contractor proceeds with the changed work.

How is overhead calculated on a change order?

Overhead is typically calculated as a percentage of direct costs (labor + materials + subcontractors + equipment). Common overhead rates range from 10–20%, covering indirect costs like insurance, office expenses, supervision, and project management time. Many public contracts cap overhead at 15%.

What is the difference between overhead and profit markup?

Overhead covers the indirect costs of running the business — insurance, office rent, management salaries, tools and vehicles. Profit is the contractor's margin above all costs. In the standard formula, profit is applied to direct costs plus overhead, so the total markup compounds slightly. For example, 15% overhead + 10% profit on $10,000 direct cost = $1,500 overhead + $1,150 profit = $12,650 total.

What is a reasonable profit margin on a change order?

Typical contractor profit margins on change orders range from 5–15%. Many contracts — especially public or government projects — specify a maximum overhead and profit (O&P) cap, often 15% overhead and 10% profit. Private commercial contracts may allow higher margins. Always review your contract's change order provisions before submitting.