Not by default, and the usual replacement story works the other way. If you already have a furnace and an aging central air conditioner, a new heat pump is both a heating appliance and a new cooling appliance. Its SEER2 (and your climate’s cooling load) determines the summer bill; its HSPF2 and your rates determine the winter bill. A higher-SEER2 heat pump can cut cooling kWh enough to help the year, even when the heating unit cost does not beat gas at the EIA average. The case where summer “cancels” winter savings is different: you add cooling you did not have, or you replace a still-efficient AC and then run a heat pump that is more expensive to heat with than the furnace you kept or removed.
A labeled sketch, not a typical house: suppose cooling is 4,000 kWh/year on the old AC and would be 3,000 kWh on the new heat pump, a 1,000 kWh decrease. At the 2025 U.S. average 17.23¢/kWh that is about $172 of summer savings. Whether winter goes the other way is the heating-unit-cost question already in the state tables — sometimes the furnace still wins on heat, sometimes not. Add the two seasons; do not let a single shoulder-month bill decide.
If you did not previously have air conditioning, the new cooling kWh are a new load and should be budgeted as such. Put your rates and, if you have them, last year’s cooling kWh and heating therms into the calculator and into a simple summer subtraction, and read SEER2 versus older ratings with the same care as the SEER2-versus-CEER page.
This is not a permit calculation, a utility approval, or a substitute for a licensed electrician, HVAC contractor, or the authority having jurisdiction. Panel Headroom is an independent educational site. It is not a utility, a certification body, or a contractor. Electrical and generator work that is done incorrectly can cause fire, shock, or carbon monoxide poisoning. Use the adopted electrical code and manufacturer instructions; pull permits where required.