Enter upfront costs and household size to compare total 10-year cost between tankless and standard tank water heaters.
Tankless units also last longer (often 20 years vs 10-13 for tanks) and take up less space — factors worth weighing beyond pure 10-year cost.
Tankless heaters cost roughly 2-3× more upfront and save around 15% on energy versus a standard tank, so the payback math depends heavily on household hot water demand and how long you'll own the home. Larger households with high hot water use close that gap faster than a single person living alone. See our full running cost calculator for the underlying energy estimate.
Not from tank depletion like a standard heater, but a tankless unit has a maximum flow rate — running two hot showers and a dishwasher simultaneously can exceed it depending on the unit's size.
The higher upfront cost usually needs 7-10+ years of energy savings to fully pay back, so if you won't own the home that long, a standard tank is often the more cost-effective choice.