What changed after 2025
The federal Section 25C Energy Efficient Home Improvement Credit is not available for property placed in service after December 31, 2025. That means a heat pump, central air conditioner, furnace, or qualifying water heater installed in 2026 or later should be priced without a federal 25C credit. The relevant date is when the equipment is placed in service, not when a proposal is signed or a deposit is paid. Homeowners should not accept a 2026 sales proposal that subtracts an expired federal credit from the advertised project cost.