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 Outdoor Tankless Water Heaters 2026: Rinnai, Rheem & Eccotemp Compared
We compared the best outdoor tankless water heaters of 2026 — Rinnai V65eN, Rinnai V53DeN, Rheem ECO200XELN-3, and the off-grid Eccotemp L10. See our picks by GPM, BTU, UEF, and price for wall-mount and portable outdoor installs.
Best PicksBest Navien Tankless Water Heaters 2026: NPE-240A2 vs NPE-210A2 vs NPE-180A2 vs NPE-180S2
We ranked every current Navien NPE-2 tankless water heater for 2026 — the flagship NPE-240A2, mid-size NPE-210A2, compact NPE-180A2, and the no-pump NPE-180S2. Real GPM, UEF, prices, and the A2-vs-S2 decoder that determines whether you're paying for a built-in recirculation pump.
ComparisonsCondensing vs Non-Condensing Tankless Water Heater 2026: Which Wins on Cost?
Condensing vs non-condensing gas tankless water heaters compared on UEF efficiency, venting cost, unit price, and total installed cost — with the vent-run rule that decides which one actually costs less.
Buying GuidesTankless Water Heater Installation 2026: Steps, Permits, and DIY vs. Pro
What actually happens during a tankless water heater installation — realistic timelines from a tankless-to-tankless swap to a full tank conversion, the permit and code rules that trip up DIYers, and the honest answer on when to hire a licensed pro.
Best PicksBest Recirculating Pump for a Tankless Water Heater (2026): Skip the Ones Built for Tanks
Most recirculating pumps on the shelf at Home Depot are built for tank water heaters and explicitly say so. We compare the Rinnai Control-R, Metlund/Taco D'MAND, and Chilipepper on-demand pumps that actually work with tankless — and name the two popular models that don't.
ComparisonsRinnai vs Navien Tankless Water Heater 2026: RX199iN vs NPE-240A2 Compared
Rinnai Sensei RX199iN vs Navien NPE-240A2 compared on flow, efficiency, warranty, price, and built-in recirculation — plus which one to buy if instant hot water matters more than the sticker price.
Why Trust TanklessHeaterLab?
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.