How much does it cost to replace an HVAC system?

A full HVAC replacement (furnace + central AC, like-for-like) costs $7,500–$18,000 installed in 2026. A heat pump (replaces both furnace AND AC) runs $12,000–$22,000 — stacking options are HEEHRA ($8,000 income-qualified) and state utility rebates ($1,500–$4,000 in MA/CT/RI/NY/CA); the federal 25C credit ($2,000) expired Dec 31, 2025. Cold-climate heat pumps (Mitsubishi Hyperheat, Daikin VRV) cost 15–25% more but maintain capacity below 0°F. Oil-to-heat-pump conversions in the Northeast can still stack $8,000–$12,000 in incentives, bringing out-of-pocket near a like-for-like furnace replacement.