Short answer
About 8 to 12 years for a standard tank, according to Fixr. ENERGY STAR cites 13 to 15 years for heat pump water heaters. Hard water, high temperature settings, high water pressure and a used up anode rod shorten the life; flushing and anode checks help a tank reach the top of its range. A tank leaking from its body or bottom is at the end and must be replaced.
Typical life by type
Water heater lifespan
| Type | Typical life | Source |
|---|---|---|
| Tank (gas or electric) | 8 to 12 years | Fixr |
| Heat pump (hybrid) tank | 13 to 15 years | ENERGY STAR |
A.O. Smith’s consumer guide gives a wider 8 to 20 years across all types (A. O. Smith). Warranties are a hint, not a promise: retail listings show the same tank size in 6, 9 or 10 year versions.
Signs a tank is near the end
- Water at the base or a leak from the tank body. Corrosion has gone through the steel, and A. O. Smith says that cannot be repaired. See leaking water heater.
- Rust colored hot water (with cold water clear) points to corrosion inside the tank.
- Popping or rumbling means hardened sediment on the bottom.
- An anode rod worn to bare wire. Once it is gone, the tank itself corrodes. Anode rod guide.
- Less hot water than it used to make, from sediment taking up space or a failed element or dip tube.
What makes a tank last longer
- Check the anode rod every few years and replace it before it is used up. Rheem says an annual check can add years of life (Rheem). How to replace it.
- Flush once a year, every six months with hard water (Rheem). How to flush.
- Control pressure. A working expansion tank on a closed system stops pressure spikes every time the tank heats.
- Set a sensible temperature. 120 F is DOE’s recommendation for most homes.
Plan the replacement
When a tank is past about 10 years and showing signs, get quotes while it still works. ENERGY STAR recommends planning a replacement ahead of failure to avoid a leaky tank cleanup and emergency call rates (ENERGY STAR). Costs are in the replacement cost guide, and a drain pan plus a leak alarm buy time in the meantime.
See leak alarms with automatic shutoff
Questions people ask
How do I tell how old my water heater is?
Read the serial number on the data label. Most makers encode the manufacture year and month in it, often in the first four characters, but each brand uses its own format. Search the brand name with “serial number age” or check the maker’s website.
Should I replace a 10 year old water heater that still works?
Not automatically. Check for rust colored hot water, rumbling, moisture at the base and the state of the anode rod. If any of those show up on an older tank, plan the replacement before it leaks.
Do gas or electric water heaters last longer?
Electric tanks are often said to outlast gas ones because there is no burner heat on the tank bottom, but we have not found a major source that measures it. Water quality and upkeep matter more than fuel.
Does flushing a water heater make it last longer?
It removes the sediment that settles on the tank bottom. Rheem recommends flushing once a year, or every six months with hard water, and says checking the anode rod can add years of life.
Sources
- Fixr, Water heater installation cost (2026)
- ENERGY STAR, Ask the experts: what goes into the cost of installing a heat pump water heater
- A. O. Smith (hotwater.com), What to do when your hot water heater is leaking (maker)
- Rheem, How to keep tank and tankless water heaters running at peak performance (maker)
- Rheem, How often to flush your water heater and how to do it (maker)
Last reviewed October 29, 2026. Models, codes and listings change; check your heater’s manual and your local code, and follow the maker’s instructions.