Water heaters
How long does a water heater last?
Updated · Editorial team; not yet technically reviewed
Short answer
A standard tank water heater commonly lasts around 8 to 12 years, and less with hard water or no maintenance. Tankless units often last longer, commonly 15 years or more with regular descaling. Plan a replacement when a tank passes about 10 years, and replace it promptly if the tank itself leaks or the water turns rusty.
How to find your heater's age
The rating plate on the side of the heater lists a serial number, and most manufacturers encode the manufacture date in it, often as a letter for the month and digits for the year, or the year as the first digits. The manufacturer's website or support line can decode it. A permit sticker or the install date written on the tank also helps.
Typical lifespans
| Type | Typical life | What shortens it |
|---|---|---|
| Gas or electric tank | About 8–12 years | Hard water, never flushed, high pressure, depleted anode |
| Tankless | Often 15–20 years | Skipped descaling in hard water |
| Heat pump (hybrid) | Similar to or longer than a standard tank | Clogged air filter, condensate problems |
Signs it's near the end
- Water seeping from the tank body. See water heater leaking.
- Rusty hot water. See brown or rusty water.
- Loud rumbling from hardened sediment.
- Running out of hot water much faster than it used to. See no hot water.
- Repairs on a tank older than about 10 years.
Making it last
- Flush sediment yearly, more often with hard water.
- Have the anode rod checked every few years and replaced when it's mostly consumed.
- Keep house pressure below 80 psi, with an expansion tank on closed systems.
- Set the thermostat to about 120 °F unless there's a reason to go higher.
Common questions
Should I replace a water heater before it fails?
Many homeowners replace a tank past about 10 years on their own schedule, especially if it's in an attic, closet or finished space, where a failure does the most damage.
General information; codes vary by location. See our editorial standards.