How Much Does an Electric Water Heater Cost to Run?
An electric tank water heater costs about $61 a month at the US average rate. Compare tank, tankless and heat pump models with real numbers.
A standard electric tank water heater uses roughly 4,000 kWh a year for a household of four — about $61 a month, or $727 a year, at the US average rate of 18.44¢/kWh. On an all-electric home it is usually the second-largest item on the bill after heating and cooling.
It is also the load with the single biggest available cut. Swapping a resistance tank for a heat pump water heater typically removes about $500 a year without changing your hot water habits at all.
- Per month
- —
- Per day used
- —
- kWh / year
- —
Why a 4,500 W element costs what it does
An electric tank heater has two 4,500 W elements, but they never fire together — the thermostat interlock allows only one at a time. Effective continuous draw is therefore 4,500 W, at a duty cycle of roughly 10% averaged over a day.
Two separate things drive that duty cycle:
- Hot water you actually use. Showers dominate. A 10-minute shower at 2.0 GPM uses about 20 gallons, of which roughly 13 are hot — around 2.2 kWh, or 41¢.
- Standby loss. The tank keeps 50 gallons at 120°F around the clock, losing heat through the jacket continuously. On an older tank this is 10–20% of total consumption for water nobody used.
Tank vs tankless vs heat pump
| Water heater type | Watts | Duty | kWh/yr | Cost/yr |
|---|---|---|---|---|
| Electric water heater (tank) | 4,500 W | 10% | 3,942 | $727 |
| Tankless water heater (electric) | 24,000 W | 1% | 2,943 | $543 |
| Heat pump water heater | 550 W | 25% | 1,204 | $222 |
The tankless figure surprises people. Tankless heaters eliminate standby loss, which is real but modest — they do not change the physics of heating water. Heating 13 gallons from 55°F to 120°F takes the same energy whether it happens in a tank or on demand.
A heat pump water heater does not generate heat — it moves it from the surrounding air into the tank, delivering roughly three units of heat per unit of electricity. That is a genuine ~65% cut, typically $500 a year at average rates. The trade-offs: it needs about 700–1,000 cubic feet of air space, it cools and dehumidifies the room it sits in (a bonus in a humid basement, a problem in a heated closet), and it is slower to recover after heavy use.
A whole-house electric tankless unit draws 24,000–28,000 W. That commonly requires three 40 A double-pole breakers and a service upgrade to 200 A or more. The electrical work frequently costs more than the heater. Gas tankless does not have this problem; electric tankless very often does.
Annual cost by state
| State | Rate | Cost | vs US avg | |
|---|---|---|---|---|
| Idaho | 12.35¢ | $487 | −240 | below average |
| Texas | 16.44¢ | $648 | −78.8 | below average |
| Florida | 15.17¢ | $598 | −129 | below average |
| Ohio | 19.52¢ | $769 | +42.6 | near average |
| Pennsylvania | 21.55¢ | $850 | +123 | above average |
| New York | 29.93¢ | $1,180 | +453 | above average |
| California | 33.25¢ | $1,311 | +584 | above average |
| Hawaii | 52.00¢ | $2,050 | +1,323 | above average |
What actually reduces the bill
Ranked by saving per dollar spent:
- Lower the thermostat to 120°F. Many are shipped at 140°F. Each 10°F reduction cuts standby loss by 3–5%, and 120°F is the DOE recommendation — hot enough to be safe, cool enough to reduce scald risk. Free, saves $25–$40 a year.
- Fix dripping hot taps. A drip at one per second wastes roughly 1,300 gallons a year, much of it heated. Near-free, saves $20–$40.
- Insulate the first 6 feet of hot pipe. Foam sleeves cost a few dollars and reduce the heat lost between tank and tap. $15, saves $10–$20 a year.
- Add a tank blanket if the tank is warm to the touch. Modern tanks are well insulated and gain little; pre-2005 tanks gain a lot. $30, saves $20–$50.
- Low-flow showerheads. Going from 2.5 to 1.8 GPM cuts hot water use by about 28% with a good modern head. $25, saves $60–$100.
- Flush sediment annually. Sediment insulates the lower element from the water, forcing longer run times. Free, saves 5–10%.
Frequently asked questions
How much does it cost to run an electric water heater per month?
About $61 a month for a family of four at the US average rate. A single person typically runs $25–$35; a family of six, $85–$110. In California the same family-of-four usage costs about $111 a month.
Is a tankless water heater cheaper to run?
Somewhat, but less than the marketing suggests. Tankless eliminates standby loss — typically 10–20% of a tank heater's consumption — but heating the water itself takes the same energy. Expect a 10–25% saving, not a halving. A heat pump water heater saves far more.
What temperature should I set my water heater to?
120°F. That is the US Department of Energy recommendation: hot enough to inhibit bacterial growth in the tank, cool enough to reduce scald risk, and meaningfully cheaper than 140°F.
How much does a 10-minute shower cost?
Roughly 41¢ in water heating at the US average rate, assuming a 2.0 GPM showerhead and a 65°F temperature rise. A 1.8 GPM head brings that to about 37¢; a 2.5 GPM head pushes it past 51¢.
Keep reading
a Clothes Dryer
An electric dryer costs about 50¢ per load and $104 a year at the US average rate. Compare vented, heat pump and line drying.
$104typical per yeara Hot Tub Cost to Run
A typical hot tub costs $40–$60 a month in electricity at the US average rate. See what drives the number and how cover condition changes it.
$565typical per yeara Refrigerator Cost to Run
A modern fridge costs about $8 a month to run. A pre-2001 model costs three times that — often more per year than a new one costs to buy.
$97.0typical per year