Heat pump or gas furnace? The honest 2026 comparison

The heating decision of the decade, reduced to one sentence: a heat pump delivers warmth at a fraction of the electricity a furnace's resistance equivalent would need, while a gas furnace delivers heat from cheaper fuel with simpler technology - and which wins your bill depends on your local prices, your climate and your house. Both keep a home equally warm; the differences are cost, carbon and installation.

The efficiency maths, honestly

A gas furnace burns fuel at roughly 80-95% efficiency (that is the AFUE rating). A heat pump does not burn anything - it moves existing heat, delivering roughly three to four units of heat per unit of electricity in mild conditions (the COP), dropping toward two in hard freezes. Comparing bills therefore needs prices: at average US rates (electricity near 18-19 cents/kWh, gas around a dollar-or-so per therm), a good heat pump usually matches or beats a mid-efficiency furnace for running cost, and it wins by miles against electric resistance heating. Where gas is cheap and electricity dear, the furnace can still win the annual bill. UK readers: with the cap-priced electricity at 26p and gas at about 7p, the running-cost race is genuinely close - which is why schemes subsidising heat-pump installs exist, and why any decision starts with your actual tariffs.

The installation reality

A furnace swap into existing flues and ducts is a days-long job. An air-source heat pump is also usually a one-to-three-day retrofit for homes with ducts (or ductless mini-splits without), but it costs several times a furnace replacement up front, and the honest answer on price is: it varies too much to quote - get local quotes and check the incentive schemes that currently apply (US federal and state credits; the UK's Boiler Upgrade Scheme grant). Sizing and insulation matter as much as the box: the insulation-first rule is what lets a smaller, cheaper system heat the same house.

Who each actually suits

Heat pump: homes without a gas connection (all-electric houses have the most to gain), households replacing both heating and cooling (it is the AC too), moderate climates - and cold-climate models now handle hard winters, at reduced efficiency in the worst weeks. Furnace: homes with existing ducts, cheap gas, and a working furnace near end-of-life where a like-for-like swap is the low-drama option; pairing it with good draught-proofing and the setback habit matters whichever way you go. The honest tiebreaker for most households: if the furnace dies mid-winter, the emergency replacement is a furnace; if you are planning ahead, price the heat pump with incentives before deciding - and for the smaller-room version of the same question, the one-room maths handles the space-heater end of the market.