How much does mold remediation cost?
This Old House reports that professional mold remediation typically costs about $1,200 to $3,750, with an average around $2,300. Small, contained jobs can cost $500 to $1,500. Large or whole-house jobs can reach $10,000 to $30,000. Prices are national figures from March 2026, and your price depends on the factors below.
Cost by size of the affected area
Size is the biggest cost driver. This Old House puts typical remediation at about $10 to $25 per square foot of affected area, which works out like this:
| Affected area | Typical cost range |
|---|---|
| 50 sq ft | $500 to $1,250 |
| 100 sq ft | $1,000 to $2,500 |
| 200 sq ft | $2,000 to $5,000 |
| 500 sq ft | $5,000 to $12,500 |
The EPA groups mold jobs into small (under 10 square feet), medium (10 to 100 square feet) and large (over 100 square feet). Medium and large jobs need full containment and air filtration.
Cost by location in the home
| Location | Typical cost range |
|---|---|
| Bathroom | $500 to $1,000 |
| Attic | $1,000 to $4,000 |
| HVAC system | $3,000 to $10,000 |
| Whole house | $10,000 to $30,000 |
Attic and HVAC jobs cost more because they are hard to reach, need more containment, and often involve removing insulation or coordinating with an HVAC contractor. See our HVAC and attic mold service.
What else affects the price
- Hidden mold. Mold inside walls or under flooring needs demolition to reach.
- Material type. Mold on framing can be cleaned. Mold on drywall and insulation is removed and replaced.
- The moisture source. An active leak must be fixed and dried, which adds water damage restoration costs.
- Rebuild. Replacing drywall, insulation and flooring after removal is usually priced separately.
- Testing. Independent clearance testing is an added cost.
Why waiting costs more
Mold spreads as long as its moisture source remains. The EPA advises drying wet materials within 24 to 48 hours to prevent growth. A leak caught and dried quickly can avoid remediation entirely, while one left for weeks can turn a small job into a large one. Our guide on how fast mold grows explains the timeline.
How to compare mold remediation quotes
- Ask what containment and air filtration are included.
- Ask how they'll find and fix the moisture source.
- Make sure removal of moldy porous materials is in the scope, not just spraying.
- Check the company's Arizona ROC license at roc.az.gov if any repair work is included.
- Ask whether clearance testing is recommended and who would do it.
When to call a professional
We inspect first, find the moisture source and give you a written scope before any remediation starts, so you know the size of the job and the cost.