Compare Tankless Water Heaters

Closely matched tankless water heaters side by side, 114 pairs in all. Each pair is scored the same way, with the independent tests and specs that separate them. See the full ranking.

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FirstChoose a product…A.O. Smith Adapt ATHR-199M – $2,346.08Camplux Climatech 7 CA686W – $629.12Camplux WA686M – $559.99Eccotemp 7GB Builder Grade – $499Eccotemp SmartHome SH22i – $499Gasland Gasmart E CE686 – $629.99Mizudo GEN 3 199K – $1,199Noritz NRC661-DV – $1,280.09Rheem IKONIC S11i – $1,847.43Rheem RTG-70DV – $653.77Rheem RTG-95DV – $1,201.29Rheem RTGH-95DV – $1,411.70Rinnai RE140e – $884.10Rinnai RE199e – $1,280.79Rinnai RE199i – $1,280.79Rinnai Sensei RX160i – $1,298.43Rinnai Sensei RX199i – $1,532.79Rinnai V53De – $741.65ThermoMate CZ750NG – $739.99ThermoMate RTC68iN – $1,099.99Bosch Tronic 4000 C 10 – $251.99Bosch Tronic 4000 C 8 – $229Bosch Tronic 6100 C 18 – $585.46Bosch Tronic 6100 C 27 – $636.60Camplux TEW18 – $278.95EcoSmart ECO 11 – $244.78EcoSmart ECO 36 – $699EcoSmart ECO 8 – $219EcoSmart ECOS 18 – $449EcoSmart ECOS 27 – $549Rheem RTEX-06T – $189Rheem RTEX-11 – $268.99Rheem RTEX-24 – $549Stiebel Eltron DHX 12-2 Trend – $266.14Stiebel Eltron Tempra 15 Plus – $619Stiebel Eltron Tempra 20 Trend – $544.43Stiebel Eltron Tempra 24 Trend – $514.23Stiebel Eltron Tempra 29 Trend – $639.99Stiebel Eltron Tempra 36 Trend – $749Westinghouse WET-24K-G – $499.99vsSecondChoose a product…A.O. Smith Adapt ATHR-199M – $2,346.08Camplux Climatech 7 CA686W – $629.12Camplux WA686M – $559.99Eccotemp 7GB Builder Grade – $499Eccotemp SmartHome SH22i – $499Gasland Gasmart E CE686 – $629.99Mizudo GEN 3 199K – $1,199Noritz NRC661-DV – $1,280.09Rheem IKONIC S11i – $1,847.43Rheem RTG-70DV – $653.77Rheem RTG-95DV – $1,201.29Rheem RTGH-95DV – $1,411.70Rinnai RE140e – $884.10Rinnai RE199e – $1,280.79Rinnai RE199i – $1,280.79Rinnai Sensei RX160i – $1,298.43Rinnai Sensei RX199i – $1,532.79Rinnai V53De – $741.65ThermoMate CZ750NG – $739.99ThermoMate RTC68iN – $1,099.99Bosch Tronic 4000 C 10 – $251.99Bosch Tronic 4000 C 8 – $229Bosch Tronic 6100 C 18 – $585.46Bosch Tronic 6100 C 27 – $636.60Camplux TEW18 – $278.95EcoSmart ECO 11 – $244.78EcoSmart ECO 36 – $699EcoSmart ECO 8 – $219EcoSmart ECOS 18 – $449EcoSmart ECOS 27 – $549Rheem RTEX-06T – $189Rheem RTEX-11 – $268.99Rheem RTEX-24 – $549Stiebel Eltron DHX 12-2 Trend – $266.14Stiebel Eltron Tempra 15 Plus – $619Stiebel Eltron Tempra 20 Trend – $544.43Stiebel Eltron Tempra 24 Trend – $514.23Stiebel Eltron Tempra 29 Trend – $639.99Stiebel Eltron Tempra 36 Trend – $749Westinghouse WET-24K-G – $499.99Compare

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• Gas 50
• Electric 46
• Across fuels 18

Best Gas Tankless Water Heaters

• Rheem RTG-95DV vs Rheem RTGH-95DV
• Rheem IKONIC S11i vs Rinnai Sensei RX199i
• Rheem IKONIC S11i vs Rheem RTGH-95DV
• Rinnai RE199i vs Rinnai Sensei RX199i
• Rheem RTGH-95DV vs Rinnai RE199e
• Rheem RTGH-95DV vs Rinnai RE199i
• Eccotemp 7GB Builder Grade vs Rheem RTG-70DV
• Rheem RTG-70DV vs Rheem RTG-95DV
• Eccotemp 7GB Builder Grade vs Gasland Gasmart E CE686
• Gasland Gasmart E CE686 vs Rheem RTG-70DV
• Gasland Gasmart E CE686 vs ThermoMate CZ750NG
• Rheem RTG-95DV vs Rinnai RE199e
• Rheem RTG-95DV vs Rinnai RE199i
• Rheem RTGH-95DV vs Rinnai Sensei RX160i
• A.O. Smith Adapt ATHR-199M vs Rinnai Sensei RX199i
• Rinnai RE199e vs Rinnai RE199i
• Camplux WA686M vs ThermoMate CZ750NG
• Camplux WA686M vs Gasland Gasmart E CE686
• Rheem RTG-95DV vs Rinnai Sensei RX160i
• Rinnai Sensei RX160i vs ThermoMate CZ750NG
• A.O. Smith Adapt ATHR-199M vs Rheem IKONIC S11i
• Rinnai RE199e vs Rinnai Sensei RX160i
• Rheem RTGH-95DV vs ThermoMate RTC68iN
• Mizudo GEN 3 199K vs Rinnai Sensei RX199i
• Camplux WA686M vs Rinnai Sensei RX160i
• Camplux Climatech 7 CA686W vs Eccotemp 7GB Builder Grade
• Camplux Climatech 7 CA686W vs Rheem RTG-70DV
• Rheem RTG-95DV vs ThermoMate RTC68iN
• ThermoMate CZ750NG vs ThermoMate RTC68iN
• Mizudo GEN 3 199K vs Rheem IKONIC S11i
• Rinnai RE199e vs ThermoMate RTC68iN
• Rinnai RE199i vs ThermoMate RTC68iN
• Mizudo GEN 3 199K vs Rinnai RE199e
• Mizudo GEN 3 199K vs Rinnai RE199i
• Camplux Climatech 7 CA686W vs Camplux WA686M
• Eccotemp 7GB Builder Grade vs Eccotemp SmartHome SH22i
• Eccotemp SmartHome SH22i vs Rheem RTG-70DV
• Rinnai Sensei RX160i vs ThermoMate RTC68iN
• A.O. Smith Adapt ATHR-199M vs Mizudo GEN 3 199K
• Camplux Climatech 7 CA686W vs Rinnai RE140e
• Camplux Climatech 7 CA686W vs Eccotemp SmartHome SH22i
• Eccotemp 7GB Builder Grade vs Noritz NRC661-DV
• Eccotemp SmartHome SH22i vs Rinnai RE140e
• Camplux Climatech 7 CA686W vs Rinnai V53De
• Camplux Climatech 7 CA686W vs Noritz NRC661-DV
• Rinnai RE140e vs Rinnai V53De
• Eccotemp SmartHome SH22i vs Rinnai V53De
• Noritz NRC661-DV vs Rinnai RE140e
• Eccotemp SmartHome SH22i vs Noritz NRC661-DV
• Noritz NRC661-DV vs Rinnai V53De

Best Electric Tankless Water Heaters

• EcoSmart ECO 36 vs Stiebel Eltron Tempra 36 Trend
• EcoSmart ECO 36 vs Stiebel Eltron Tempra 29 Trend
• Stiebel Eltron Tempra 29 Trend vs Stiebel Eltron Tempra 36 Trend
• EcoSmart ECO 36 vs EcoSmart ECOS 27
• EcoSmart ECOS 27 vs Stiebel Eltron Tempra 36 Trend
• Stiebel Eltron Tempra 24 Trend vs Stiebel Eltron Tempra 29 Trend
• EcoSmart ECO 36 vs Rheem RTEX-24
• Stiebel Eltron Tempra 29 Trend vs Westinghouse WET-24K-G
• Rheem RTEX-24 vs Stiebel Eltron Tempra 36 Trend
• EcoSmart ECOS 27 vs Stiebel Eltron Tempra 29 Trend
• Stiebel Eltron Tempra 24 Trend vs Westinghouse WET-24K-G
• Rheem RTEX-24 vs Stiebel Eltron Tempra 29 Trend
• Stiebel Eltron Tempra 20 Trend vs Stiebel Eltron Tempra 24 Trend
• Bosch Tronic 6100 C 27 vs Stiebel Eltron Tempra 24 Trend
• EcoSmart ECO 11 vs Stiebel Eltron Tempra 20 Trend
• EcoSmart ECOS 18 vs Stiebel Eltron Tempra 24 Trend
• Bosch Tronic 6100 C 27 vs Westinghouse WET-24K-G
• Rheem RTEX-24 vs Westinghouse WET-24K-G
• EcoSmart ECOS 27 vs Rheem RTEX-24
• EcoSmart ECO 11 vs EcoSmart ECOS 18
• EcoSmart ECO 8 vs Stiebel Eltron DHX 12-2 Trend
• EcoSmart ECOS 18 vs EcoSmart ECOS 27
• Bosch Tronic 6100 C 27 vs Rheem RTEX-24
• EcoSmart ECOS 18 vs Stiebel Eltron Tempra 20 Trend
• Camplux TEW18 vs Stiebel Eltron DHX 12-2 Trend
• Bosch Tronic 4000 C 10 vs EcoSmart ECO 8
• Bosch Tronic 6100 C 27 vs EcoSmart ECOS 18
• Bosch Tronic 6100 C 18 vs EcoSmart ECO 11
• EcoSmart ECO 11 vs Stiebel Eltron Tempra 15 Plus
• Bosch Tronic 4000 C 10 vs Stiebel Eltron DHX 12-2 Trend
• Bosch Tronic 4000 C 10 vs Camplux TEW18
• EcoSmart ECO 11 vs Rheem RTEX-11
• Bosch Tronic 4000 C 8 vs EcoSmart ECO 8
• Bosch Tronic 6100 C 18 vs Stiebel Eltron Tempra 20 Trend
• Stiebel Eltron Tempra 15 Plus vs Stiebel Eltron Tempra 20 Trend
• Bosch Tronic 6100 C 18 vs Bosch Tronic 6100 C 27
• EcoSmart ECO 8 vs Rheem RTEX-06T
• Stiebel Eltron DHX 12-2 Trend vs Stiebel Eltron Tempra 15 Plus
• Bosch Tronic 4000 C 8 vs Stiebel Eltron DHX 12-2 Trend
• Rheem RTEX-11 vs Stiebel Eltron DHX 12-2 Trend
• Camplux TEW18 vs Rheem RTEX-11
• Bosch Tronic 4000 C 10 vs Bosch Tronic 4000 C 8
• Bosch Tronic 4000 C 10 vs Rheem RTEX-06T
• Bosch Tronic 6100 C 18 vs Stiebel Eltron Tempra 15 Plus
• Rheem RTEX-11 vs Stiebel Eltron Tempra 15 Plus
• Bosch Tronic 4000 C 8 vs Rheem RTEX-06T

Across fuels

• Eccotemp 7GB Builder Grade vs Stiebel Eltron Tempra 36 Trend
• Stiebel Eltron Tempra 36 Trend vs ThermoMate CZ750NG
• Camplux WA686M vs EcoSmart ECO 36
• Gasland Gasmart E CE686 vs Stiebel Eltron Tempra 36 Trend
• EcoSmart ECO 36 vs Rinnai Sensei RX160i
• EcoSmart ECO 36 vs ThermoMate RTC68iN
• Eccotemp 7GB Builder Grade vs EcoSmart ECOS 27
• Rheem RTEX-24 vs Rheem RTG-70DV
• Rinnai RE140e vs Stiebel Eltron Tempra 24 Trend
• Camplux Climatech 7 CA686W vs EcoSmart ECOS 27
• Rinnai RE140e vs Westinghouse WET-24K-G
• Eccotemp SmartHome SH22i vs EcoSmart ECOS 27
• Bosch Tronic 6100 C 27 vs Rinnai RE140e
• Rheem RTEX-24 vs Rinnai RE140e
• Rinnai V53De vs Stiebel Eltron Tempra 24 Trend
• Rinnai V53De vs Westinghouse WET-24K-G
• EcoSmart ECOS 27 vs Noritz NRC661-DV
• Bosch Tronic 6100 C 27 vs Rinnai V53De