Find the Best Tankless Water Heater for Your Home
We compare and rank gas, propane, and electric tankless water heaters on flow rate, efficiency, and real install cost — so you get endless hot water without the guesswork.
Latest Reviews & Guides
Best Westinghouse Tankless Water Heater 2026: Two Different Manufacturers, One Name
Westinghouse-branded tankless water heaters come from two unrelated manufacturers under license — HTP's gas condensing commercial-grade units and Fogatti's electric Apolo consumer line — specs and prices on the Apolo Mini 3.5kW, Apolo Performance 18kW, and Apolo 27kW Whole House models.
Best PicksTankless Water Heaters on Amazon (2026): The Authorized-Seller Catch
Amazon carries the widest tankless water heater selection of any retailer on this site — electric EcoSmart and Rheem RTEX units, plus Rinnai's gas lineup. But Navien isn't on Amazon at all, and buying Rinnai from the wrong seller can void your warranty.
Best PicksBest Tankless Water Heater Heat Exchanger Replacements 2026: Rinnai, Rheem, Navien
A replacement tankless water heater heat exchanger isn't a universal part, and it isn't cheap — genuine OEM units run $440 to over $1,100 depending on brand. Here's the correct part for Rinnai, Rheem, and Navien, and when replacing it costs more than just buying a new unit.
Best PicksBest Tankless Water Heater for a Boat (2026): The Mounting Location Matters More Than the Model
We compared the best tankless water heaters for boats in 2026 — Camplux BW264-N, Eccotemp L10, and the Stiebel Eltron Mini 3-1. The real decision isn't GPM, it's where the propane unit vents, after real carbon-monoxide recalls on boats.
Best PicksBest Tankless Water Heater for a Barn (2026): Why Built-In Freeze Protection Isn't Enough
We compared the best tankless water heaters for barns and wash racks in 2026 — Camplux BW264-N, Eccotemp L10, and Rheem RTEX-13. The catch: a barn is one of the likeliest places to lose the power that every whole-home unit's freeze protection depends on.
Buying GuidesSmart Tankless Water Heater: Which Brands Actually Build In WiFi? (2026)
'Smart' and 'WiFi-enabled' don't mean the same thing across brands. Rheem and Navien's current flagships build WiFi into the unit at no extra cost — Rinnai and Noritz sell it as a separate module you have to add on.
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Spec-Driven Reviews
We rank on measured GPM flow rate, UEF efficiency, and real-world install cost — not marketing claims.
Tankless Specialists
Gas, propane, condensing, and electric on-demand units — we know Rinnai from Rheem and UEF from GPM.
Every Budget
From under-$200 point-of-use electric units to premium condensing whole-home systems — clearly labelled.
Updated for 2026
Prices, picks, efficiency ratings, and tax-credit notes kept current.