Heating · Montana
How Much Does It Cost to Run an Electric Water Heater in Montana?
The short answer
Running a 4,500W electric water heater in Montana costs about $0.67 an hour. At 3 hours a day, that’s roughly $61.56 a month and $739 a year.
That’s based on Montana’s average residential rate of 15.0¢/kWh (EIA, July 2026), 18% below the US average.
Source: U.S. EIA, July 2026 data · Updated
Electric Water Heater cost by daily use in Montana
| Daily use | kWh/month | Per day | Per month | Per year |
|---|---|---|---|---|
| 1 hour/day | 136.9 | $0.67 | $20.52 | $246 |
| 2 hours/day | 273.8 | $1.35 | $41.04 | $492 |
| 4 hours/day | 547.6 | $2.70 | $82.08 | $985 |
| 8 hours/day | 1,095.1 | $5.40 | $164 | $1,970 |
| 12 hours/day | 1,642.7 | $8.09 | $246 | $2,955 |
| 24 hours/day | 3,285.4 | $16.19 | $492 | $5,909 |
Montana vs other states
At typical use, an electric water heater costs $739 a year in Montana — $1,627 less than in Hawaii and $112 more than in Louisiana.
Montana has the 14th-cheapest residential electricity of the 50 states and DC. electricity prices in Montana · all states ranked
Electricity price trend in Montana
15.0¢/kWh in July 2026 — ▲ +5.0% from a year earlier.
How to lower the cost of running an electric water heater
Electric tank water heaters keep 40–80 gallons of water hot around the clock, switching their heating elements on whenever you use hot water or the tank cools down. The elements are typically 4,500W, and total run time for a family is roughly 2–4 hours a day, which is why water heating is often the second-biggest line on an all-electric home's bill. Heat pump water heaters do the same job with 2–3 times less electricity.
- Set the tank to 120°F (49°C) — many ship at 140°F, which wastes energy.
- Insulate the first few feet of hot water pipe and fix dripping hot taps.
- Consider a heat pump water heater when your tank needs replacing — they use about a third of the electricity.
Questions
Frequently asked questions
How much does it cost to run an electric water heater for 24 hours in Montana?
Running a 4,500W electric water heater for 24 hours uses about 108 kWh, which costs about $16.19 at Montana’s average rate of 15.0¢/kWh.
How many kWh does an electric water heater use per month?
At 3 hours a day, a typical electric water heater uses about 411 kWh a month. In Montana that costs $61.56.
Is it expensive to run an electric water heater in Montana?
Montana has the 14th-cheapest residential electricity of the 50 states and DC at 15.0¢/kWh — cheaper than most. Running an electric water heater here costs about $739 a year at typical use, compared with $902 at the national average rate.
What is the electricity rate in Montana right now?
The average residential electricity rate in Montana was 15.0¢ per kWh in July 2026, according to the latest EIA data — up 5.0% from a year earlier.
How many hours a day does an electric water heater run?
For a typical household, about 2–4 hours a day in total, spread across showers, laundry and dishes, plus short reheats to make up for standby heat loss.
Electric Water Heater costs in nearby states
Other appliances in Montana
Cheapest and priciest states
Sources & method
- Electricity rates: U.S. Energy Information Administration, Electric Power Monthly — average residential retail price, July 2026 (latest available). Retrieved .
- CO₂: EIA State Electricity Profiles, 2024 emissions rate of in-state power generation.
- Default usage for electric water heater: 3 hours a day. Typical power 4,500W.
- Formulas, duty cycles and limitations: methodology. Data download: open data (CC BY 4.0).