Short answer
Keep the fuel you have unless the numbers clearly favor a switch. Gas tanks reheat faster, so a smaller tank can deliver the same first hour rating, and they usually cost less to run than a standard electric tank. Electric tanks need no vent and are simpler to install. Fixr’s 2026 installed ranges are $700 to $2,700 gas and $500 to $3,500 electric. If you are electric, a heat pump model is the efficient choice.
Side by side
Gas vs electric tank water heaters
| Gas tank | Electric tank | |
|---|---|---|
| Installed cost (Fixr 2026) | $700 to $2,700 (propane $700 to $2,500) | $500 to $3,500 |
| Reheat speed | Faster, burner under the tank | Slower, two elements |
| Needs | Gas line and a vent (flue or power vent) | Dedicated 240 volt circuit for most full size tanks |
| Running cost | Usually lower than standard electric | Usually the highest of the three |
| Upkeep | Burner and vent checks, pilot or igniter, anode, flushing | Elements and thermostats, anode, flushing |
| Power cut | Many atmospheric models keep heating | No hot water |
When gas wins
- You already have gas and a sound vent. A like-for-like swap is the cheapest job.
- Your busiest hour is heavy. Faster reheat means a 40 or 50 gallon gas tank can keep up where an electric tank of the same size cannot.
- Gas is cheap where you live. Compare your rates before you decide.
When electric wins
- No gas line, or no flue. Electric tanks need no venting at all.
- Tight or indoor spaces where a vent is hard to run.
- You want a heat pump. Heat pump water heaters are electric; ENERGY STAR says a family of four could save nearly $550 a year compared with a standard electric tank (ENERGY STAR). See the heat pump guide.
Switching fuel
Fixr notes that converting between fuels often brings in a licensed electrician for wiring or a panel upgrade, or a specialist for a gas line, on top of normal labor of about $300 to $1,500. Get quotes for the whole job before deciding on running costs alone. More in the replacement cost guide.
Venting, briefly
Atmospheric gas tanks send exhaust up a flue by natural draft. Power vent tanks use a fan and can vent out through a wall where there is no chimney; Fixr puts adding one, with its electrical connection, at $300 to $1,000. Venting is safety work: a blocked or leaky vent can spill carbon monoxide.
Questions people ask
Is gas or electric cheaper to run?
It depends on your local gas and electric rates. Standard electric tanks are usually the most expensive to run. ENERGY STAR says a certified heat pump water heater is typically at least 3 to 4 times more efficient than standard electric and gas models.
Which heats water faster?
Gas. A burner puts heat into the water faster than electric elements, so gas tanks recover faster and reach a higher first hour rating for the same tank size.
Can I switch from gas to electric?
Yes, but budget for a 240 volt circuit and possibly a panel upgrade, plus capping the gas line and the vent. Fixr notes fuel switches often need a licensed electrician or gas specialist, which adds cost.
Do gas water heaters work in a power outage?
Many standard atmospheric gas tanks with a standing pilot keep working without power. Power vent and electronic ignition models need electricity. Check your model’s manual.
Sources
Last reviewed October 29, 2026. Models, codes and listings change; check your heater’s manual and your local code, and follow the maker’s instructions.