What Plumbers Want You to Know About the Life Expectancy of Water Heaters

Most water heaters don’t fail suddenly. They give you signs long before they stop working. The problem is, most homeowners miss those signs or assume the unit will last forever.

The average water heater lasts between 8 and 12 years. But how long yours lasts depends on how it was installed, how well it’s maintained, and whether you’re paying attention to the early warnings.

Here’s what licensed plumbers want every homeowner to understand about the real lifespan of a water heater, how to spot trouble early, and when it’s time to replace it before it becomes a bigger problem.

How Long Does a Water Heater Really Last?

If you’ve got a traditional tank model, you’re looking at 8 to 12 years of solid use. That’s assuming it was installed correctly and you’ve flushed it at least once in its life.

In homes with hard water or high usage, heaters wear out faster. On the flip side, if you’re in a small household and the system was sized right, it might run well into year 15.

Tankless water heater systems last longer, usually up to 20 years, but only with regular maintenance. If they’re never flushed, buildup ruins the heat exchanger early.

The Signs Most People Miss

Here’s what we see on the job all the time: people don’t act until the tank leaks or the water turns cold. But you don’t need to wait that long.

Here are the signs that tell you your water heater is reaching the end:

1. It’s 10+ years old

That’s the average. If your tank is older than that, you should at least be thinking about your replacement plan. Waiting until it fails gives you no time to compare options or prepare.

2. You’re running out of hot water faster

The inside of your tank is filled with sediment. That leaves less room for hot water. You’re still using the same amount, but now it runs out sooner.

3. The water looks rusty

Rust-colored water from the hot side usually means the inside of the tank is corroding. That happens when the anode rod is used up and no longer protects the tank.

4. You hear rumbling or banging

That’s not just noise—it’s hardened mineral deposits reacting to heat. It’s also a sign that the system is working harder than it should, and likely overheating.

5. There’s moisture or water near the base

If you see water where the tank meets the floor, don’t assume it’s just condensation or a fitting. It could mean the tank itself is cracked—and if it is, there’s no patching it.

When to Replace It (Before It Fails)

Here’s the honest answer: if you’re already seeing signs and your tank is past year 10, you’re on borrowed time. Replacing it now avoids emergency charges, cleanup costs, and the stress of losing hot water when you need it.

Smart timing gives you:

• A choice between tank and tankless
• Time to upgrade fittings, add expansion tanks, or meet code
• Better availability and pricing
• A cleaner, safer install

Waiting means rushing and rushed replacements usually skip steps that matter.

Can You Make It Last Longer?

If your current heater still works, there are a few ways to get more life out of it:

• Flush it once a year to remove sediment
• Check or replace the anode rod every few years
• Keep the thermostat around 120°F
• Have a licensed plumber inspect it for leaks or wear before problems show up

Skipping maintenance doesn’t just shorten lifespan; it also cuts efficiency and raises your energy bills.

What Plumbers Really Want You to Know

A water heater doesn’t have to fail before you replace it. If you’ve had yours for over a decade, and you’re seeing the signs, it’s smarter and cheaper to plan a water heater replacement now.

We’ve handled too many calls where a cracked tank flooded a garage or utility closet. And in almost every case, the signs were there. They just got ignored.

If you’re not sure where your system stands, call Rockwater Plumbing. We’ll take a look, give you a straight answer, and help you figure out if it’s time to replace or just time to flush it and keep going.