How Much Does a Tankless water heater Cost to Run? (2026 Calculator)
Typical setup: 18000 W · 1 h/day · $0.180/kWh
Daily
$3.24
Monthly
$97.08
Yearly
$1181.14
Quick rate
Daily cost
$3.24
Monthly cost
$97.08
+$0.00 vs typical
Yearly cost
$1181.14
kWh / month
540.0 kWh
Local monthly estimate: $97.08 · U.S. average equivalent: $97.08
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ad-after-calculator Quick answer
A typical tankless water heater uses about 18000 W and costs about $3.02/day or $90.72/month at the U.S. average rate of $0.17/kWh, assuming 1 hours of use per day. At the same rate, costs range from about $2.02/day (12000 W) to $4.03/day (24000 W).
State explorer
Quickly spot cheapest, highest, and near-average monthly costs.
Top 10 cheapest
Top 10 highest
- Hawaii $214.87
- Massachusetts $168.26
- Maine $165.94
- California $163.57
- Rhode Island $162.76
- New York $153.20
- Connecticut $152.82
- New Hampshire $142.13
- Alaska $137.81
- District of Columbia $128.09
Cost by state (monthly)
At typical 18000 W and 1 h/day. Rates from our dataset (see methodology ). Open a state for a dedicated calculator page.
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ad-after-state-table Wattage range
| Level | Watts | Est. monthly @ avg rate |
|---|---|---|
| Low | 12000 W | $64.72 |
| Typical | 18000 W | $97.08 |
| High | 24000 W | $129.44 |
Energy saving tips
- Turn the appliance off as soon as you are done using it.
- Avoid leaving the appliance in high-power standby modes.
- Unplug the appliance if it is rarely used.
- Only heat the room you are in and close doors to unused rooms.
FAQ
- Most tankless water heater units fall between 12000 W and 24000 W, with 18000 W as a typical operating value for estimates.
- Our estimates use 18000 W as the typical wattage, within a reported range of 12000–24000 W.
- At typical use (1 hours/day at 18000 W), the estimate is about 18.00 kWh/day and 540.0 kWh/month at the U.S. average rate.
- With 1 hours/day and 18000 W, this appliance uses about 18.00 kWh per day.
- At 1 hours/day, the monthly estimate is about 540.0 kWh per month.
- Per hour, the typical draw is about 18.000 kWh (at 18000 W).
- At the U.S. average electricity rate of $0.17/kWh, the typical daily cost is about $3.02/day for 1 hours/day.
- At the U.S. average electricity rate of $0.17/kWh, the typical monthly cost is about $90.72/month at 1 hours/day.
- Running for one hour at 18000 W costs about $3.02/hour (using 0.17 $/kWh as the U.S. average).
- With typical use (1 hours/day at 18000 W), the estimate is about $3.02/day or $90.72/month at the U.S. average rate.
- The estimate is about 540.0 kWh per month, which corresponds to roughly $90.72/month at the U.S. average rate. Your real bill depends on your rate and runtime.
- Use energy-saving tips tailored to this appliance. For example: Turn the appliance off as soon as you are done using it. — reducing kWh reduces the bill at your local rate.