How long does a water heater last?
A tank water heater typically lasts 8–12 years, a tankless unit 15–20 years or more, and a heat pump tank about 10–15 years. Hard water, heavy use and skipped maintenance shorten all of these.
Rheem and A.O. Smith both put tanks at 8–12 years and tankless units at 15–20 years. Home inspectors’ guidance (InterNACHI) runs lower, at 6–12 years for a conventional tank and 10 for on-demand units, while a 2012 Department of Energy report gave tanks 10–15 years and tankless up to 20. None of the sources separates gas from electric tanks.
Rheem gives heat pump water heaters about 10–15 years, more with upkeep. Whatever the type, a leak from the tank body means the end of its life, and manufacturers suggest planning a replacement around year 10 rather than waiting for a failure.
Confidence: multi-source · Based on 6 cited sources.
Sources
- Measure Guideline: Transitioning to a Tankless Water Heater · U.S. Department of Energy, Building America (IBACOS)
- Water Heater Lifespan: When to Repair vs. Replace · Rheem
- How to Extend the Life of Your Rheem Heat Pump Water Heater · Rheem
- 5 Signs Your Water Heater Is Going Bad · Rheem
- How Long Do Tankless Water Heaters Last? · A.O. Smith
- Standard Estimated Life Expectancy Chart for Homes · InterNACHI
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Water Heater Replacement Cost: What a Fair Quote Looks LikeBy Purchasd Research. We compared installed-cost ranges from seven ad-supported cost guides (This Old House, Fixr, PickHVAC, Modernize, Home Grail, Thumbtack and Bob Vila), one completed-install dataset (Rewiring America’s analysis of over 1,200 California heat pump water heater installs), published permit fees from three local governments, code text from a Utah utility district and the California statute, ENERGY STAR and DOE technical guidance, and manufacturer pages for lifespan and repair advice. We read seven Reddit threads from November 2025 to September 2026 in full, recording only prices commenters actually stated. Cost-guide ranges were treated as published estimates, not measurements, and Reddit prices as self-reports. Home Depot and Lowe’s pages block automated reading, so their terms come from search excerpts and are marked unverified. Purchasd received no payment, referral fee or consideration from any manufacturer, retailer, plumber or cost-guide publisher for this research. Most cost guides earn from contractor leads or product sales, This Old House’s headline figures come from Home Depot data, and the manufacturers quoted sell replacement units; each source is labeled by bias. Purchasd has not obtained or tested quotes itself.