What HVAC replacement costs in O Fallon
Construction pricing in Missouri runs 6% below the national average, so HVAC replacement here typically lands between $8,930 and $15,510 installed, before rebates.
Figures are modeled from 2026 national baselines adjusted by a Missouri cost factor of 0.94. They are estimates for comparison, not quotes — your property, access and material choices move the real number.
HVAC Contractors serving O Fallon
Ranked by Google review volume. Listings are sourced from public business data; those marked Verified member have claimed and confirmed their listing with us.
- Swiss Air Heating & Cooling, LLC
- AAA Home Services
- Absolute Comfort Systems Heating & Air Conditioning
- Renaud Brothers Heating & Cooling
- Lennox Stores (PartsPlus)
- Hoff Heating & AC
- Sierra Mechanical
- Air Rescue
- One Hour Heating & Air Conditioning
- RK Heating & Cooling
- Faszold Heating and Cooling
- Stay Cool Climate Control
- Rippelmeyer Services
- Craigco Heating & Cooling, LLC
- KirbnJays Heating & Cooling
- NORDYNE LLC
- St. Louis Realty
- Rogers Comfort Systems
- Aire Serv Heating & Air Conditiong
We don't rank by who pays us. Always confirm a contractor's license and insurance before hiring.
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