Most water heater comparisons start with tank versus tankless. This one starts with the fuel, because fuel is the choice you live with on every bill for the next decade — and it's the choice that's hardest to undo. Switching tank styles later is a plumbing job. Switching fuels means new venting or new wiring, sometimes both. Here's how gas and electric stack up on purchase price, annual energy cost, recovery rate, and the installation limits that quietly decide the question for many houses.
| Factor | Gas (natural gas) | Electric (resistance tank) |
|---|---|---|
| 50-gal tank unit price | $550–$900 | $400–$650 |
| Installed total, like-for-like swap | $1,200–$1,800 | $800–$1,200 |
| Typical annual energy cost | $250–$400 | $450–$700 |
| Recovery rate (90°F rise) | Roughly 30–40 gallons per hour | Roughly 20–25 gallons per hour |
| First-hour rating, 50-gal tank | About 80–90 gallons | About 65–70 gallons |
| Typical lifespan | 8–12 years | 10–15 years |
| Venting | Required — flue to outside | None |
| Works in a power outage? | Standing-pilot models, yes; electronic ignition, no | No |
| Placement limits | Needs gas line, vent path, combustion air | Needs a 240V circuit and panel capacity |
Propane sits between the two on most rows: the hardware and venting look like natural gas, but the fuel usually costs more per unit of heat, narrowing gas's running-cost edge. Oil-fired heaters, now rare outside parts of the Northeast, run higher still on service costs.
Electric wins the day-one math without much argument. The unit costs less, there's no flue to run or inspect, no gas line to connect, and labor for a straightforward swap commonly lands a few hundred dollars under a gas install. The full installed ranges — permits, pans, and disposal included — are broken down in our guide to water heater replacement costs, and fuel is one of the biggest levers in it.
Gas catches up only if the infrastructure is already in the room. A like-for-like gas swap, vent and line already in place, is a routine job. A conversion to gas is not: a new gas line run commonly adds $500–$1,500, and venting work several hundred more. The mirror-image trap waits on the electric side. A tank swap needs a dedicated 240-volt circuit, typically 25–30 amps — trivial if the old heater was electric, but a panel that's already full can turn an electric conversion into a $1,500–$3,000 panel upgrade. Neither conversion is a reason to panic; both are reasons the fuel question gets answered by an installer quote, not a spec sheet.
Natural gas delivers heat at a lower cost per BTU than resistance electricity in most of the country, and the table shows the result: a typical household spends roughly $250–$400 a year heating water with gas, versus $450–$700 with a standard electric tank. That's a $200–$300 yearly gap in gas's favor — enough to repay a gas swap's higher install price in about 2–3 years, and to repay a conversion only over a much longer stay.
Two cautions keep that math honest. First, rates vary more than equipment does: in regions with cheap hydroelectric power or expensive delivered gas, the gap shrinks or flips, so run the comparison with your own utility rates, not national averages. Second, the electric column above is resistance heating. A heat pump water heater uses roughly a third of the electricity of a resistance tank and can land near or below gas on yearly cost — at a higher purchase price and with space and noise quirks of its own. It's an electric option worth pricing, not a footnote.
Recovery is where households feel the fuel difference daily. After the tank's stored hot water runs down, a gas burner reheats at roughly 30–40 gallons per hour; electric elements manage about 20–25. In practice, a gas 50-gallon tank supports back-to-back morning showers noticeably better than the same-size electric, and its first-hour rating — stored water plus what it reheats in that hour — runs about 15–20 gallons higher.
Households solve slow electric recovery with size: stepping from a 50-gallon to an 80-gallon electric tank covers the morning rush by storage instead of speed, and the bigger tank still usually costs less installed than a gas conversion. This storage-versus-speed trade-off is the same one at the heart of tankless versus tank water heaters — read that comparison next if endless hot water, rather than fuel, is the itch.
Gas needs: a gas line with enough capacity for the heater's BTU rating alongside the furnace and stove, a vent path that meets code for slope and termination, and enough combustion air in the room. Tight mechanical closets and long vent runs rule gas out in some floor plans, and sealed-combustion or power-vent models that work around those limits cost more.
Electric needs: a 240-volt circuit, breaker space, and panel capacity with headroom. A 100-amp service already feeding an electric range, dryer, and AC may not have room — and tankless electric heaters, which can draw 80–150 amps on their own, are off the table entirely for many panels. An electrician's load calculation answers this in one visit.
Either fuel needs: the basics people forget mid-crisis — a drain pan where a leak would damage finishes, an expansion tank on a closed system, and a temperature-and-pressure relief valve piped to a safe discharge. When a heater dies suddenly, the triage is the same regardless of fuel, and our guide to no hot water in the house covers the checks to run before assuming the unit is dead at all.
Gas line and vent already in place: gas, in most regions. Lower yearly cost, faster recovery, and the swap is routine. This is the default for a reason.
All-electric house, no gas service on the street: electric — and price a heat pump model before defaulting to resistance. Running a gas line to the property for one appliance almost never pays back.
Big household, heavy morning demand: gas for recovery speed, or a larger electric tank sized for storage. Avoid a standard 50-gallon resistance tank; it'll be the daily complaint.
Tight closet, odd corner, or placement far from any vent path: electric. No flue and no combustion air requirements open up locations gas can't use.
Frequent power outages: a standing-pilot gas model keeps delivering hot water when the grid is down. Electronic-ignition gas and all electric models stop with the power.
Fuel decides the next decade of bills; the tank style is a detail by comparison. Where gas infrastructure already exists, gas is usually cheaper to run and faster to recover, and it earns back its higher install price within a few years. Where it doesn't exist, electric's simple install wins — and a heat pump model can close most of the running-cost gap. Price your own house, with your own rates, before the old heater makes the decision under time pressure.
In most of the US, yes — roughly $250–$400 a year for gas versus $450–$700 for a standard electric resistance tank, at typical rates. The exception is regions with unusually cheap electricity or pricey gas, and heat pump electric models, which cut electric costs by about two-thirds and can beat gas on the yearly bill.
Commonly $500–$1,500 for the gas line run alone, plus venting work and the higher unit and labor cost — pushing a conversion well past a like-for-like swap. Against yearly savings of roughly $200–$300, payback typically takes most of a decade, so conversions make the most sense during a larger remodel.
Gas. A gas tank recovers roughly 30–40 gallons per hour versus about 20–25 for electric elements, which is why a 50-gallon gas tank posts a first-hour rating around 80–90 gallons against 65–70 for the same-size electric. Electric households compensate with a larger tank.
Yes, and it's often simpler than the reverse: no vent to remove beyond capping, and the gas line gets capped by a pro. The checkpoint is electrical — the panel needs capacity and a dedicated 240-volt circuit. An electrician's load calculation settles whether the swap is easy or needs a panel upgrade first.
Only standing-pilot models. They need no electricity to fire, so hot water continues through an outage. Gas models with electronic ignition or power venting, and every electric model, stop when the power does — worth knowing in outage-prone areas.