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Side-by-Side Comparison

Gas vs. Electric
Water Heater Cost Calculator

Enter your actual utility rates and see exact annual operating costs, 10-year totals, and CO₂ impact — including heat pump electric. Results update instantly.

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Gas Water Heater
Natural gas tank or tankless
US average: $1.30/therm. Check your bill for your local rate.
Conventional gas: 0.67 · High-eff tank: 0.76 · Condensing tankless: 0.92
Electric Water Heater
Standard electric or heat pump
US average: $0.17/kWh. HI: $0.43, WA: $0.10. Check your bill.
Standard electric: 0.92 · Heat pump: 3.50–4.50
Gas Water Heater
Annual energy cost
Monthly cost
10-year energy cost
Annual CO₂ emissions
Therms/year
Effective UEF
Electric Water Heater
Annual energy cost
Monthly cost
10-year energy cost
Annual CO₂ emissions
kWh/year
Effective UEF
Annual Savings with Lower-Cost Option

Matching Water Heaters

Gas vs. Electric Water Heater — Common Questions

Is a gas or electric water heater cheaper to operate?
At US average utility rates ($1.30/therm for gas, $0.17/kWh for electric), a conventional gas tank water heater costs $250–$400/year to operate while a conventional electric tank runs $500–$800/year. However, a heat pump electric water heater costs only $150–$280/year — cheaper than gas in most US markets. The answer depends on your local rates: in low-electricity states like Washington, Tennessee, or Idaho, heat pump electric wins. In states with very high electricity rates like Hawaii, gas holds an advantage.
Is a heat pump water heater better than gas?
For most US households, yes. A heat pump water heater with UEF of 3.5–4.0 moves heat from the air rather than generating it, making it 3–4× more efficient than a standard electric resistance tank. Even compared to gas, heat pump electric typically wins on annual operating cost unless local electricity rates exceed $0.22–$0.25/kWh (the breakeven point vs. $1.20/therm gas). The federal §25C tax credit and utility rebates further improve the economics.
Which water heater type is best in cold climates?
In very cold climates, gas tanks perform consistently year-round because combustion efficiency does not depend on ambient temperature. Heat pump water heaters lose efficiency when ambient air drops below 40°F — they fall back to resistance heating mode. However, most heat pump models installed in conditioned spaces (basements, garages) still outperform gas in cold climates because indoor air rarely drops below 40°F. Condensing gas tankless is an excellent cold-climate option for its reliability and efficiency.
What does UEF mean for water heaters?
UEF (Uniform Energy Factor) is the federal efficiency metric for water heaters, replacing the older EF rating. It measures how efficiently a unit converts energy to hot water. A conventional gas tank has UEF around 0.60–0.70. A condensing gas tankless unit reaches 0.87–0.96. A standard electric tank is 0.90–0.95. A heat pump water heater achieves UEF 3.5–4.5, meaning it delivers 3.5–4.5 units of heat energy for every unit of electricity consumed. Higher UEF equals lower operating cost.

Gas vs. Electric Water Heaters: The Real 2026 Cost Comparison

The gas vs. electric water heater debate has fundamentally changed since 2020. For most of the previous century, the answer was simple: gas is cheaper to run, electric is cheaper to buy. That calculus has shifted dramatically with the rise of heat pump water heaters and significant drops in their installed cost, making electric now the cost leader in most US markets when you account for operating costs over the unit's lifespan.

Running the Real Numbers at National Average Rates

Using US Energy Information Administration (EIA) 2024 residential utility averages — $1.30/therm for natural gas and $0.17/kWh for electricity — here is how the three main types compare annually for a typical 50-gallon, 4-person household using approximately 64 gallons of hot water per day:

Water Heater TypeUEFAnnual Energy UseAnnual CostAnnual CO₂
Conventional gas tank0.67~248 therms$3232,900 lbs
High-efficiency gas tank0.76~218 therms$2842,550 lbs
Condensing gas tankless0.92~180 therms$2342,110 lbs
Standard electric resistance0.92~4,860 kWh$8263,985 lbs
Heat pump water heater3.50~1,277 kWh$2171,047 lbs

The headline number: a heat pump water heater at national average electric rates costs $217/year to operate — less than every gas option. The standard electric tank at $826/year is the most expensive option by a wide margin. This is why the DOE's 2010s efficiency standards effectively pushed manufacturers away from large standard electric resistance tanks.

Where Gas Still Wins: The Rate Breakeven Analysis

The gas advantage persists in specific local markets. To calculate the breakeven point where gas becomes cheaper than a heat pump: divide the gas cost per BTU by the heat pump's COP. At $1.20/therm, gas costs $0.01149/BTU. A heat pump with UEF 3.5 and electricity at $0.17/kWh costs $0.01392/BTU equivalent — gas wins. At $0.15/kWh, the heat pump wins. At $0.20/kWh, gas regains the edge.

The breakeven electricity rate vs. $1.20/therm gas is approximately $0.175–$0.19/kWh depending on heat pump UEF. States where electricity rates exceed this threshold consistently — Hawaii ($0.43/kWh), California ($0.30/kWh), Massachusetts ($0.29/kWh) — still favor gas. States below this rate — Washington ($0.10/kWh), Idaho ($0.11/kWh), Tennessee ($0.12/kWh) — strongly favor heat pump electric.

Regional Price Volatility: Natural Gas Varies 4× Across the US

The other major variable is gas price volatility. While the national average sits around $1.30/therm, residential natural gas prices span an enormous range: Utah and Wyoming at $0.80/therm, Hawaii at $3.50/therm (propane equivalent), New England at $1.80–$2.20/therm in winter. Gas prices also spike sharply during extreme cold events — Uri in Texas (2021) and similar events have pushed spot prices to 10–20× normal for short periods.

Electric rates, by contrast, are more stable and regulated. The long-term trend in many regions is toward cheaper renewable electricity, particularly in states with large solar or wind capacity additions. Homeowners in these markets who install heat pump water heaters now are well-positioned for further operating cost declines.

Environmental Impact: Which Is Greener?

CO₂ accounting for gas is straightforward: natural gas combustion produces approximately 11.7 lbs of CO₂ per therm. A conventional gas tank at 248 therms/year generates about 2,900 lbs of CO₂ annually — not counting upstream methane leakage, which EPA estimates adds 25–30% to the effective climate impact of natural gas.

Electric CO₂ depends heavily on your grid's carbon intensity. The EPA average grid emission factor is approximately 0.82 lbs CO₂/kWh. A standard electric tank using 4,860 kWh/year produces about 3,985 lbs of CO₂. A heat pump at 1,277 kWh/year produces only 1,047 lbs — less than any gas option. As grids decarbonize (the average US grid is about 40% cleaner than in 2005), electric water heaters become progressively greener over their 10–15 year lifespans without any hardware change.

Heat Pump Water Heaters and the IRA $300 Tax Credit

The Inflation Reduction Act of 2022 dramatically improved the economics of heat pump water heaters. Section 25C provides a 30% federal income tax credit, capped at $300 per year, for qualifying ENERGY STAR-certified heat pump water heaters installed through December 31, 2032. This applies to the unit cost (not labor). At a typical installed cost of $1,200–$1,800 for the unit, the credit returns $300 — meaningful on a $400–$600 operating cost saving per year versus a standard electric tank.

Many utilities compound this with additional rebates. Mass Save (Massachusetts) offers $750. PSEG (NJ, LI) offers $400. Xcel Energy (MN, CO) offers $350. Pacific Gas & Electric offers up to $1,000 through its heat pump water heater program. Combined incentives can reduce net cost of a heat pump water heater installation by $700–$1,500, improving the payback period to 2–4 years versus a standard electric replacement.

Hard Water Effects on Both Types

Hard water (above 7 GPG) affects gas and electric water heaters differently. In gas tanks and tankless units, scale buildup on heat exchanger surfaces reduces efficiency by creating an insulating layer that forces the burner to work harder. In electric tanks, scale accumulates directly on the lower resistance heating element, causing the distinctive "rumbling" sound and eventually burning out elements prematurely — the average electric element fails 3–5 years earlier in 15+ GPG water than in soft water. Heat pump water heaters are more resilient because the primary heating happens via the refrigerant coil, not a direct-contact element, though the backup resistance element is still vulnerable. In hard water areas above 10 GPG, annual flushing or a point-of-use softener can extend water heater life by 3–7 years regardless of fuel type.

Bottom Line: At current national average rates, the heat pump water heater wins on annual operating cost ($217/year vs. $323/year for conventional gas). Gas still wins in high-electricity markets. Standard electric resistance tanks are the most expensive option in virtually every US market and are being phased out by DOE efficiency standards for units over 55 gallons. Use this calculator with your own utility rates for a personalized comparison.