Water heater comparisons
Tank water heaters cost less upfront ($600-$2,500 installed) and last roughly 10-15 years. Tankless costs more ($1,400-$3,900 installed, plus $150-$2,500 in conversion work), never runs out of hot water, and has a life expectancy of about 20 years. Heat pump units cost the most upfront but have the lowest operating cost of any electric option.
The honest version of this comparison: tankless is not automatically better. ENERGY STAR puts the savings for a certified gas tankless unit at about $95 per year, or $1,800 over its lifetime, versus a standard gas storage model. That is real money, but it is not transformational - and if your conversion costs land near the top of NerdWallet's $150-$2,500 range, the payback stretches well past a decade.
Tankless makes most sense when you are already replacing gas venting, when you genuinely run out of hot water today, when floor space is valuable, or when you plan to stay in the house long enough for a 20-year life expectancy to matter. Tankless makes least sense as an emergency swap for a failed tank, in a home with very hard water and no plan for descaling, or where the gas supply would need major work.
Gas versus electric is usually decided for you by what is already in the house. Changing fuel type means new supply and, for gas, new venting - both licensed, both permitted, both expensive.
Heat pump versus everything else is the comparison worth taking seriously if you are on electricity. ENERGY STAR requires UEF of 3.30 or higher for certified integrated heat pump units against roughly 0.95 for certified gas tankless, which is a large operating-cost gap. The counterweights are upfront cost, the space and air the unit needs, condensate drainage, and the loss of the federal 25C credit for 2026 installs.
Choosing water heater between the options
The judgement calls that decide the bill, before anyone quotes you.
- Compare total 15-year cost, not sticker price Install cost plus conversion work plus estimated annual running cost plus expected maintenance. Do it on paper. Salespeople compare the numbers that favor their product.
- Weigh how long you will own the house A 20-year life expectancy and a 12-year payback are only worth something to someone who is still there. If you are moving in three years, the cheap reliable tank is often the rational answer.
- Factor your water hardness into tankless Scale is the main early-failure mode for tankless heat exchangers. If your water is hard, add the cost of descaling service or a softener to the tankless column before comparing.
- Do not compare a heat pump unit against gas on efficiency alone UEF is not comparable across fuel types in dollar terms. Compare estimated annual operating cost using your own utility's rates.
All water heater comparisons
Tank vs Tankless Water Heater
Gas vs Electric Water Heater
Heat Pump vs Conventional Water Heater
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Where these figures come from
Sources last checked
- ENERGY STAR - Gas Tankless Water Heaters: Benefits and Savings · retrieved 2026-07-25
- ENERGY STAR - Residential Water Heaters Key Product Criteria · retrieved 2026-07-25
- NerdWallet - Water Heater Cost in 2026 · retrieved 2026-07-25
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