The average U.S. household with an electric resistance water heater uses 4,000–5,000 kWh per year on water heating, costing $560–$800 annually at the national average rate of $0.16/kWh. But your actual cost depends heavily on where you live — a family of four in Hawaii paying $0.40/kWh spends over $1,800 per year on water heating alone, while the same family in Louisiana at $0.10/kWh pays just $450. This state-by-state analysis shows you exactly what electric water heating costs in your area and how to dramatically cut that bill.
How Much Electricity Does a Water Heater Use?
Before diving into state costs, let's establish the baseline. The U.S. Department of Energy estimates that water heating consumes 18–20% of a home's total energy use, making it the second-largest energy expense after space heating and cooling.
Your actual electricity consumption depends on four key variables: household size, water heater efficiency (UEF), inlet water temperature (driven by geography), and usage habits.
The climate difference matters more than most people realize. In Miami (groundwater 75°F), heating water to 120°F requires a 45°F temperature rise. In Minneapolis (groundwater 42°F), the rise is 78°F — 73% more energy per gallon. This means a Minnesota household uses 25–35% more kWh for water heating than a Florida household with identical habits.
Understanding the kWh Calculation
Here's the physics behind the numbers. To heat 1 gallon of water by 1°F, you need 8.33 BTUs. One kWh equals 3,412 BTUs. So heating 50 gallons of water from 55°F to 120°F (a 65°F rise):
50 gal × 65°F × 8.33 BTU/(gal·°F) = 27,073 BTUs ÷ 3,412 BTU/kWh = 7.93 kWh
At a UEF of 0.93 (accounting for tank standby losses and conversion efficiency): 7.93 ÷ 0.93 = 8.53 kWh per day for a standard electric tank serving a typical household.
Over a year: 8.53 × 365 = 3,113 kWh for a moderate-use household in a temperate climate. Larger families and colder climates push this to 5,000–7,000+ kWh.
State-by-State Electric Water Heating Costs
The following table uses EIA residential electricity rates (early 2026 data), a family of four baseline with a standard electric resistance tank (UEF 0.93) consuming approximately 4,800 kWh per year for water heating at the national average groundwater temperature.
Electricity rates change frequently. These figures use early 2026 EIA data. Your actual rate may differ — check your most recent utility bill for the exact per-kWh charge, including delivery fees, demand charges, and surcharges that may not appear in the base rate.
The 5 Most Expensive States for Electric Water Heating
1. Hawaii — $1,896/year ($158/month)
Hawaii's isolation from mainland fuel sources pushes electricity rates to nearly 40¢/kWh — the highest in the nation. Electric water heating alone costs Hawaiian families $150+ per month. Solar water heaters (providing 60–80% of hot water needs in Hawaii's sunny climate) and heat pump water heaters offer the most dramatic savings here.
2. California — $1,368/year ($114/month)
California's aggressive renewable energy mandates, grid infrastructure costs, and wildfire-related expenses have driven rates to 28–30¢/kWh in many utility territories. Southern California Edison and PG&E customers in Tier 2+ pay even more. A heat pump water heater saving 65% on kWh translates to $800–$900/year in California — the strongest payback in the continental U.S.
3. Massachusetts — $1,320/year ($110/month)
New England's reliance on natural gas for electricity generation (with pipeline constraints driving winter price spikes) keeps rates above 25¢/kWh. Combined with cold groundwater temperatures requiring more energy per gallon, Massachusetts is among the worst states for electric resistance water heating.
4. Connecticut — $1,286/year ($107/month)
Similar dynamics to Massachusetts — high electricity rates, cold inlet water, and aging infrastructure. Connecticut homeowners with electric resistance tanks should prioritize HPWH upgrades, which can cut annual costs from $1,286 to under $400.
5. Rhode Island — $1,248/year ($104/month)
Rhode Island's rates mirror the broader New England pattern. The smallest state has some of the highest energy costs in the country, making efficiency upgrades exceptionally worthwhile.
Real-World Example — The Garcia Family (Sacramento, CA): Paying $0.30/kWh on PG&E's Tier 2 rate, their 50-gallon electric tank consumed 5,100 kWh/year for water heating, costing $1,530 annually. After switching to a Rheem ProTerra XE65 heat pump water heater (1,400 kWh/year), their annual water heating cost dropped to $420 — saving $1,110 per year. With $3,400 installed cost minus $1,020 federal tax credit, the $2,380 net cost paid for itself in just 2.1 years.
The 5 Cheapest States for Electric Water Heating
1. Louisiana — $504/year ($42/month)
Abundant natural gas and nuclear power keep Louisiana's electricity rates near 10.5¢/kWh. Combined with warm groundwater (65–72°F), electric water heating costs are among the nation's lowest. Even so, a heat pump water heater would save $300+/year.
2. Idaho — $518/year ($43/month)
Hydroelectric power from the Columbia River basin gives Idaho some of the cheapest electricity in the country at around 10.8¢/kWh. Low rates reduce (but don't eliminate) the case for HPWH upgrades — savings drop to $250–$350/year.
3. Washington — $528/year ($44/month)
Washington benefits from the same hydroelectric resources as Idaho. At 11.0¢/kWh, electric water heating is affordable even with a standard resistance tank. The HPWH payback period stretches to 6–8 years in Washington, making it a lower-priority upgrade than in high-cost states.
4. Utah — $552/year ($46/month)
Coal and natural gas generation keeps Utah's rates low at 11.5¢/kWh. However, Utah's cold groundwater (45–52°F) pushes kWh consumption higher than southern states, partially offsetting the low rate.
5. Wyoming — $566/year ($47/month)
Wind and coal power keep Wyoming rates affordable. Like Utah, cold groundwater increases per-gallon energy requirements, but the low per-kWh rate keeps total costs manageable.
Electric vs. Gas vs. Heat Pump: Cost Comparison by State
To give you the full picture, here's how the three main water heater types compare in representative states.
Look at the "Heat Pump" column. In every single state listed, a heat pump water heater is cheaper to operate than a standard electric tank — and it's competitive with or cheaper than natural gas in most states. The only states where gas tanks clearly win on operating cost are those with very cheap gas (under $0.85/therm) AND moderate electricity (under $0.13/kWh).
What Drives Your Electric Water Heating Cost
1. Electricity Rate (Biggest Factor)
The per-kWh rate is the single largest variable. A family in Hawaii paying $0.395/kWh spends 3.6× more than the same family in Louisiana at $0.105/kWh — even if both use identical water heaters with identical habits. There's nothing you can do about your base rate, but you can dramatically reduce kWh consumption (see strategies below).
2. Household Size and Habits
Every additional person adds roughly 800–1,200 kWh per year to water heating consumption. Specific habits matter too: a 15-minute shower uses 2–3× more hot water than an 8-minute shower. Running a dishwasher on "heated dry" adds unnecessary energy. Washing clothes in warm water instead of cold can add 1,000+ kWh annually.
3. Inlet Water Temperature
You can't change your groundwater temperature, but understanding it helps explain why your bill might be higher than national averages. Every 10°F colder your inlet water, expect roughly 10–15% higher kWh consumption for water heating.
4. Water Heater Efficiency and Age
A new electric tank (UEF 0.93) is about 10% more efficient than a 10-year-old unit due to improved insulation and element design. A heat pump water heater at UEF 3.50 uses 60–75% less electricity than any resistance tank. An aging unit with significant sediment buildup can lose 15–25% of its rated efficiency.
5. Thermostat Setting
The DOE recommends 120°F. Every 10°F above that increases energy consumption by approximately 3–5%. Some households set their tank to 140°F — this wastes 6–10% more energy than necessary and increases scalding risk.
6. Standby Losses
A standard electric tank loses 1–2°F per hour through its walls when no hot water is being drawn. Over a full day, this standby loss can account for 15–25% of total energy consumption, especially in smaller households where the tank sits idle for long stretches.
How to Reduce Your Electric Water Heating Cost
Ranked by potential savings, from most to least impactful:
1. Switch to a Heat Pump Water Heater (Saves 50–75%)
This is the single most impactful upgrade. A HPWH uses 1,000–1,800 kWh/year versus 4,000–5,000+ kWh for a resistance tank. At the national average of $0.16/kWh, that's $480–$640 per year in savings.
Cost: $2,500–$4,500 installed ($1,750–$3,150 after federal tax credit).
Real-World Example — The Nguyen Family (Houston, TX): The Nguyens paid $0.135/kWh and used 4,600 kWh/year for their electric tank ($621/year). They installed a 65-gallon heat pump water heater (1,300 kWh/year = $176/year). Annual savings: $445. Installed cost: $3,100. Tax credit: $930. Net cost: $2,170. Payback: 4.9 years.
2. Lower the Thermostat to 120°F (Saves 3–10%)
If your water heater is set to 130°F or 140°F, dialing it down to 120°F saves 3–5% per 10°F reduction. For a family spending $700/year, that's $21–$70 annually — not huge, but it costs nothing and takes 30 seconds.
3. Install Low-Flow Fixtures (Saves 10–20%)
Replacing 2.5 GPM showerheads with 1.5 GPM low-flow models cuts shower hot water usage by 40%. A family that showers 8 times per day (collectively) at 8 minutes each saves 3,200 gallons of hot water per month. At roughly 8.3 BTU per gallon per degree of temperature rise, that's significant.
Cost: $15–$40 per showerhead. Aerators for kitchen and bath faucets: $3–$8 each.
4. Add a Tank Insulation Jacket (Saves 5–15% on standby)
If your tank feels warm to the touch, an insulation blanket ($20–$35) reduces standby heat loss by 25–45%. This saves $25–$80 per year depending on your electricity rate and ambient temperature.
5. Insulate Hot Water Pipes (Saves 2–5%)
Adding ¾" foam pipe insulation to the first 6–10 feet of hot water outlet pipe reduces heat loss during delivery. This is especially valuable for long pipe runs to distant bathrooms. Cost: $5–$20 in materials.
6. Use Cold Water for Laundry (Saves 5–10%)
Modern detergents clean effectively in cold water. Switching from warm to cold wash eliminates 7–12 gallons of hot water per load. A household doing 6 loads per week saves 2,000–3,500 gallons of hot water per year.
7. Fix Dripping Faucets (Saves 1–5%)
A hot water faucet dripping at 1 drop per second wastes approximately 1,660 gallons per year — that's $30–$100 in electricity depending on your rate. A $5 washer or cartridge repair pays for itself in days.
Time-of-Use Rates: A Hidden Opportunity
Many utilities now offer time-of-use (TOU) rate plans where electricity costs less during off-peak hours (typically 9 PM – 7 AM) and more during peak hours (4 PM – 9 PM). The spread can be significant: $0.10/kWh off-peak versus $0.35/kWh on-peak in California.
Electric water heaters — especially tanks with stored hot water — are perfect for TOU optimization. You can set a timer or use a smart water heater to heat water during off-peak hours and coast on stored hot water during peak rates.
Potential savings: 15–30% on water heating costs in markets with aggressive TOU differentials.
Real-World Example — TOU Strategy (Southern California Edison): A homeowner switched to SCE's TOU-D-PRIME rate plan (off-peak: $0.13/kWh, peak: $0.38/kWh). Using a smart timer on their heat pump water heater, they shifted 80% of water heating to off-peak hours. Average effective rate dropped from $0.25/kWh to $0.16/kWh. Annual water heating cost went from $350 (HPWH) to $224 — an additional $126/year savings on top of the HPWH efficiency gains.
Electric Water Heating Cost Trends (2020–2026)
Electricity prices have risen steadily, increasing the case for efficiency upgrades:
Electricity prices rose roughly 29% from 2020 to 2026. During the same period, heat pump water heater prices dropped 10–15% due to manufacturing scale, and the federal tax credit made them more accessible. The economics of switching from resistance electric to heat pump have never been stronger.
Key Takeaways
- National average: A family of four pays $560–$800/year for electric resistance water heating ($47–$67/month).
- Most expensive states: Hawaii ($1,896/yr), California ($1,368/yr), Massachusetts ($1,320/yr), Connecticut ($1,286/yr).
- Cheapest states: Louisiana ($504/yr), Idaho ($518/yr), Washington ($528/yr), Utah ($552/yr).
- Heat pump water heaters cut electric water heating costs by 50–75% and pay for themselves in 2–7 years after the federal tax credit.
- Free/cheap fixes — lowering thermostat, low-flow fixtures, insulation, cold-water laundry — can save $100–$300/year combined.
- Time-of-use rates offer an additional 15–30% savings for households willing to shift heating to off-peak hours.
- Electricity prices rose ~29% since 2020, making efficiency upgrades increasingly valuable each year.
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