8-12 years · 15-20+ years
Typical lifespan
| Type | Typical lifespan | Source |
|---|---|---|
| Standard tank (gas or electric) | 8-12 years | Widely-cited manufacturer/plumbing-industry consensus (Rheem, A.O. Smith, Bradford White installation guidance; InterNACHI life-expectancy chart) |
| Tankless | 15-20+ years | Same manufacturer/plumbing-industry consensus; tankless units have no tank to corrode, roughly double a standard tank's service life |
Signs you need to replace it
- !Unit is more than 10 years old
- !Leaks or moisture pooling around the base of the tank
- !Rust-colored water coming from hot taps
- !Rumbling, popping, or banging noises (sediment hardening on the heating element)
- !Inconsistent water temperature or noticeably slower recovery time
What replacement costs
Standard 40-50 gallon gas tank installed: $900-$1,900. Tankless (gas): $3,000-$4,500 installed, sometimes higher with gas-line/electrical upgrades.
Maintenance that extends its life
- Flush the tank annually to clear sediment before it hardens on the heating element
- Check/replace the sacrificial anode rod every 2-5 years (faster in hard-water areas)
- Set the thermostat to 120°F — hotter settings accelerate tank wear
FAQ
How long does a water heater really last?
A standard tank water heater typically lasts 8-12 years; a tankless unit typically lasts 15-20+ years. Hard water and lack of maintenance can shorten either significantly.
What's the first sign a water heater is failing?
Rust-colored water or a rumbling/popping noise from the tank are usually the earliest signs — both point to sediment buildup or internal corrosion, both of which get worse, not better.
Is it cheaper to repair or replace a water heater?
If the unit is past 8-10 years old and the repair involves the tank itself (not just a thermostat or heating element), replacement is usually the better financial move — tanks don't get repaired, they get patched until they leak.