What size water heater do I need?

A 1–2 person home usually needs a 40-gallon tank; 3–4 people a 50-gallon; 5 or more an 80-gallon. Tankless units are sized by gallons per minute.

Is tankless better than a tank?

Tankless heats on demand, never runs out, and lasts longer, but costs more upfront and must be sized for your climate's incoming water temperature.

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Tank size or tankless flow for your household.

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What size water heater do I need?: A 1–2 person home usually needs a 40-gallon tank; 3–4 people a 50-gallon; 5 or more an 80-gallon. Tankless units are sized by gallons per minute.
Is tankless better than a tank?: Tankless heats on demand, never runs out, and lasts longer, but costs more upfront and must be sized for your climate's incoming water temperature.