There's no universal winner — your local gas and electricity rates decide it. In most gas-served regions a gas tank costs less to run and recovers hot water about twice as fast, so it wins big families and cheap-gas markets. A standard electric tank is cheaper to buy, simpler to install, and produces no combustion — best where there's no gas or you're going all-electric. And the real efficiency play is a heat-pump water heater (3–4× a standard electric tank), which beats gas on running cost in nearly every market if you have the space for it.
This compares the fuel — gas vs electric storage tanks. Whether to go tanklessis a separate decision; see the tank vs. tankless guide. Either way, size the unit to your household with the free Water Heater Size Calculator.
⚖️ Gas vs. Electric at a Glance
Storage Tank, Head to Head
| Factor | Gas storage | Electric storage |
|---|---|---|
| Equipment only (40–50 gal) | ~$500–$900 | ~$350–$800 |
| Installed cost | ~$1,300–$3,200 | ~$950–$2,200 |
| Running cost | Usually lower (rate-dependent) | Usually higher on resistance |
| Efficiency (UEF) | ~0.58–0.70 | ~0.90–0.95 (heat-pump ~3.3–4.1) |
| Recovery | ~30–45 GPH (faster) | ~14–21 GPH |
| Lifespan | ~8–12 years | ~10–15 years |
| Needs | Gas line, venting, combustion air | 240V/30A circuit, panel capacity |
| Combustion / IAQ | CO, NOx — must be vented | None |
Prices last reviewed July 2026. Water-heater and install costs vary widely by region, fuel rates, venting, and electrical work — treat these as wide relative ranges, not quotes. Operating cost is rate-dependent; run your own utility numbers with the formula below.
💵 Running Cost: Do the Rate Math, Not the Efficiency Headline
Here's the mistake almost every article makes: it compares UEF and declares a winner. But UEF is efficiency, not cost. A gas tank posts a low UEF (~0.62) and an electric tank a high one (~0.92), yet gas usually still costs less to run — because a unit of gas energy is far cheaper than a unit of electricity in most markets. To actually compare, convert both to cost per delivered BTU:
- Electric: your $/kWh ÷ (UEF × 3.412)
- Gas: your $/therm ÷ (UEF × 100)
For scale, a standard electric-resistance tank runs on the order of $550–$600 a yearat average rates; a heat-pump water heater uses about 70% less, and per ENERGY STAR saves a family of four roughly $550/year versus a standard electric tank. That's why the honest modern answer to "go electric?" is usually "go heat-pump" (below).
🚿 Recovery & First-Hour Rating — Size by the Right Number
Gas burners put out 30,000–75,000 BTU/hr; electric elements are equivalent to a fraction of that, so gas recovers hot water roughly twice as fast (~30–45 GPH vs ~14–21 GPH). The number that actually predicts running out mid-shower isn't tank gallons — it's the First-Hour Rating (FHR) on the yellow EnergyGuide label, which combines usable tank volume plus recovery. Because gas refills faster, a 40-gallon gas tank often out-delivers a 50-gallon electric in the busy morning hour. Size to your peak-hour demand by FHR, not by gallons — the water heater size calculator does this for you.
♻️ The Heat-Pump Water Heater Option
A heat-pump (hybrid) water heater is the modern "electric" choice, and it changes the math. Instead of making heat with resistance elements, it moves heat from the surrounding air like a refrigerator in reverse, reaching UEF ~3.3–4.1 — 3–4× a standard electric tank, and low enough in running cost to beat gas in nearly every market. Installed cost runs about $2,800–$4,700+, with a ~3–6 year payback versus a standard electric tank.
🔧 Install, Venting & Power Outages
- Gas needs a gas line, combustion air, and venting — atmospheric (passive vertical vent, cheapest, runs in an outage, but can backdraft in tight homes), power-vent (blower through a sidewall, flexible, but needs power), or sealed direct-vent (safest inside the envelope).
- Electric needs a dedicated 240V/30A circuit and enough panel capacity — a full panel can force a $1,000–$4,000+ service upgrade.
- Switching fuels adds hidden cost. Gas→electric means a new circuit (maybe a panel upgrade) plus capping the gas line; electric→gas means a gas line and venting. Budget for it before assuming a switch saves money.
- Power outages: a standing-pilot atmospheric gas heater keeps making hot water in a blackout; power-vent gas and every electric unit do not.
📋 Code, Incentives & the 2029 Rule
- Code (local AHJ governs). T&P relief valve on every tank; a thermal expansion tank is required on a closed system (a PRV, check valve, or backflow preventer present); seismic strapping in seismic zones; gas units need combustion air (roughly 50 cu ft of room per 1,000 BTU/hr) and proper venting; heat-pump units need a condensate drain and adequate air volume.
- Federal 25C tax credit: EXPIRED December 31, 2025 (terminated by the One Big Beautiful Bill Act; IRS FS-2025-05). There is no federal credit for 2026 installs — ignore any page still claiming "30% through 2032."
- IRA rebates survived and are active in 2026 but state-administered and uneven: HEEHRA/HEAR offers up to $1,750 for a heat-pump water heater (income-qualified — full amount only below 80% of area median income), within a $14,000 household cap. Funding is limited (California's single-family rebates were fully reserved as of Feb 2026). Verify with your state energy office and utility.
- The 2029 DOE standard (compliance May 6, 2029) will effectively require heat-pump technology for most electric storage tanks over 35 gallons and raise gas standards. It governs manufacturing — it does not ban gas heaters or force you to replace an existing tank.
🎯 Which Should You Use?
- Cheap local gas + existing gas line/venting → gas (lowest running cost, cheapest like-for-like swap).
- Large family / lots of back-to-back hot water → gas (faster recovery, higher first-hour rating).
- Outage resilience matters → standing-pilot atmospheric gas.
- No gas service, all-electric or solar home, or IAQ priority → electric.
- Lowest upfront cost with a 240V circuit already there → standard electric.
- You have ~700–1,000 cu ft of space and want the lowest running cost → heat-pump water heater (and check for state rebates).
- Deciding tank vs on-demand too? → see the tank vs. tankless guide.
Estimate your Water Heater Size materials
Free water heater size calculator using the DOE first-hour-rating method — count your busiest hour's hot-water uses and get the FHR to shop for.
Estimate with the Water Heater Size Calculator →