You are probably here because you are looking for a new water heater but aren't sure which type to buy: electric or gas? You could decide on a whim, but you might regret it. In this article we compare both electric and gas water heaters so you can decide for yourself which best suits your needs.
Difference Between Electric and Gas Water Heaters
An electric water heater uses a heating element — a rod-shaped device that converts electricity into heat — submerged inside the tank. It heats the water in the center of the tank, and the heat radiates outward. A gas water heater instead burns fuel to produce a flame that heats the water from below; the cold water at the bottom warms and rises to the top, where it is drawn out. A hollow flue running up through the middle of the tank carries exhaust gas out to a vent.
Installation
Installing an electric water heater is usually easier because electricity is available in every house, while a gas line often is not. Around 50% of U.S. households have a gas supply line; if yours doesn't, adding a gas connection — plus wider vents and larger gas piping — can be expensive.
Cost of Each Type
Electric water heaters are cheaper to buy. In both categories you'll find units from about $500 at the low end to $2,000 at the high end, but on average you'll pay more for gas: roughly $600+ for electric versus $800+ for gas.
Operating Cost
Although gas heaters cost more to buy, they are cheaper to run because natural gas tends to be cheaper than electricity. On average a gas unit costs about $30 per month to operate versus about $42 for electric — a 33% difference, or about $108 more per year and roughly $1,080 over ten years for electric.
Our Top Picks
Rheem RTEX-24 Electric Tankless Water Heater
A strong electric option: endless hot water, digital temperature control, and no venting or gas line required.
Rinnai RUCS65iP Tankless Gas Water Heater
A gas option that keeps producing hot water during power outages and delivers a high 6.5 GPM flow rate.
Final Editorial Verdict
Efficiency, Safety, and Reliability
Energy efficiency: Electric heaters are actually more energy efficient — because the heating rods sit in the water, little energy is lost, whereas a gas flame wastes much of its heat as exhaust. Look for an Energy Factor (EF) above 0.82; energy-efficient gas, oil, or propane units may qualify for a federal tax credit.
Power outages: A gas water heater keeps producing hot water during an outage; an electric one cannot run without electricity.
Recovery time: Electric heaters take roughly twice as long to reheat a full tank. An 80-gallon gas unit reheats in about 1 hour 15 minutes; an electric one takes more than 2 hours.
Safety: Electric heaters are relatively safer — gas units carry a small risk of gas leaks and carbon monoxide, and sometimes require relighting a burner.
Bacterial growth: One study of 211 Quebec homes found that 40% of electric water heaters allowed Legionella contamination while none of the gas units did — the researchers concluded electric heaters were the most significant factor. Keeping your temperature high enough (see our temperature guide) helps prevent this regardless of type.
The Bottom Line
Choose electric for lower purchase price, easier installation, and better raw efficiency. Choose gas for cheaper monthly operating cost, faster recovery, and hot water during power outages. Whichever you pick, buy an energy-efficient model and set the temperature to keep bacteria in check.