How long does a water heater last?
Updated August 2026
A conventional tank water heater lasts 8–12 years. Gas tanks sit at the low end of that (8–12), electric tanks stretch a little longer (10–15) because there is no burner or flue corroding the works, and a tankless unit runs 15–20+ years since it stores no water to rust through. A heat-pump (hybrid) tank lands around 10–15. Where in the range yours ends up comes down to two things: how hard your water is, and whether anyone ever replaced the anode rod.
Lifespan by type and situation
| Type or situation | Typical lifespan | Why |
|---|---|---|
| Gas tank (atmospheric) | 8–12 years | The standard; the burner and tank steel are the wear items |
| Electric tank | 10–15 years | No combustion, so the tank itself usually decides its fate |
| Tankless (gas or electric) | 15–20+ years | No stored water to corrode; descale it yearly and most parts are replaceable |
| Heat-pump (hybrid) | 10–15 years | A tank plus a compressor: efficient, but more parts that can fail |
| Hard water, no softener | Cut 2–4 years | Scale buries the burner or elements and speeds up tank wear |
| Anode rod never replaced | Cut 3–5 years | Once the rod is spent, the tank steel is what corrodes next |
| Flushed yearly, anode checked | Top of the range | Maintenance is the difference between 8 years and 15 |
Signs yours is near the end
- Rusty or brown hot water while the cold runs clear, a sign the tank is corroding from the inside
- A rumbling, popping, or percolating sound as it heats: water boiling up through a bed of sediment
- Moisture, rust, or a small puddle around the base of the tank
- Water that runs lukewarm or runs out fast, even though nothing about your usage changed
- A manufacture date on the serial-number sticker that is 10 or more years back
- Repairs stacking up: a new element or thermostat on a tank already past 10 years
How to add years
Two habits do almost all the work. Flushing the tank once a year, twice a year in hard water, clears the sediment that insulates the burner and cooks the bottom of the tank; it is the cheapest way to reach the top of the range. Checking the anode rod every 2–3 years and swapping the $30–60 part once it is more than half consumed keeps corrosion eating the rod instead of the tank steel, which is the single most common reason a tank dies at 8 instead of 15. Softening hard water helps both jobs at once. Once a tank passes 10 years, starts leaking, or is staring down its second repair, run the math on repair versus replacement before you put another dollar into it.
What it costs to replace: plan on $1,200–2,000 installed ($2,500–4,500 for tankless). Replacing on your own schedule, before it fails, is almost always cheaper than the emergency version. The home maintenance cost calculator helps you set the money aside before it comes due.
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Track your home's systems, free for 30 daysFrequently asked questions
Does flushing a water heater actually make it last longer?
Yes, measurably. Sediment, the minerals that drop out of heated water, piles up on the bottom of the tank where it insulates the burner and forces it to run hotter and longer; on an electric tank it can bury and burn out the lower element. Flushing once a year, twice in hard water, clears that layer. It is a big part of why a maintained tank reaches 12–15 years instead of failing at 8. Pair it with an anode rod check every 2–3 years.
Which lasts longer, a gas or electric water heater?
Electric, usually by a few years. A gas tank averages 8–12 years; an electric tank often reaches 10–15, because it has no burner, no flue, and no combustion byproducts corroding the assembly, so the tank itself is the only part that has to survive. The trade-offs are slower recovery and a higher energy bill across most of the country. Either way, water hardness and anode-rod upkeep move the lifespan more than the fuel type does.
Is a 15-year-old water heater too old to keep?
For a standard tank, yes: start planning. Most tanks are on borrowed time past 12, and a 15-year-old one has a real chance of splitting at a seam and flooding whatever it sits above. If it still works you do not have to rip it out tomorrow, but budget for the swap and avoid sinking money into a big repair. Tankless is different: 15 is mid-life, and a descale plus a replacement part is usually worth it. Weigh it with the repair-or-replace guide.
What are the signs a water heater is about to fail?
Rusty or metallic-tasting hot water, a rumbling or popping tank, water that never gets fully hot or runs out fast, and any moisture, rust, or dampness around the base. A small puddle is the loudest warning of all, because tanks rarely seep for long before they let go completely. If you see standing water, or the unit is past 12 years, shut off the water supply to it and price a replacement now, not after the floor is soaked.