Best Garage Heater (2026): Electric and Propane Picks by Garage Size

Heater maker Dimplex plans on 10 watts per square foot in an insulated room. The 3 garage heaters we list that state a room size plan on 10 watts per square foot too. Measure your garage, then find its row.^[7][1]

That is for an insulated garage. If the walls are bare, the door is not insulated, or your winters are cold, buy the next size up. For a 2-car garage that means 7,500 to 10,000 W, like our 10,000 W pick.

Amps = watts ÷ volts. Your electrician sizes the breaker and wire from the heater's amps and its manual.

Electric heat: every watt becomes heat. At the U.S. average home price of 18.19¢ per kWh (EIA, January to July 2026), 100,000 Btu of heat costs about $5.33.^[4]

Propane: a gallon holds 91,452 Btu (EIA). A Big Buddy burns in the room and has no vent, so all of that heat stays in the garage. At the U.S. average home propane price of $2.69 a gallon (EIA, week of October 19, 2026), 100,000 Btu costs about $2.94, about half the price of electric heat. That is the price for delivered propane; check what your local tank refill costs.^[5]

1 lb cylinders cost far more per hour than a 20 lb tank. For more than a quick job, hook it to a 20 lb tank with the Buddy hose.^[2]

Natural gas, for a vented gas unit heater: at the U.S. average home price of $15.34 per thousand cubic feet (EIA, 2025 annual average) and 1,037 Btu per cubic foot, 100,000 Btu costs about $1.48. A heater that is 80% efficient, like the Modine Hot Dawg listing says, delivers it for about $1.85. That is under half the cost of electric heat, but the gas line, vent and a pro's install cost extra.

"Season" in the table is 160 hours: 4 hours every weekend day for 20 weeks. A thermostat cycles the heater off once the garage is warm, so most days cost less.

A garage heater that can warm the whole space runs on 240 volts, like a clothes dryer, and needs its own circuit. A hardwired heater has no plug: an electrician connects it to the breaker panel. A plug-in one needs a matching 240 V outlet, and its listing says which one.

A 5,000 W heater draws about 20.8 amps. A 10,000 W heater draws about 41.7 amps, so check that your panel has room for it. Ask the electrician to size the breaker and wire from the heater's manual.

Mount it high, on the ceiling or wall, and aim it at where you work. Keep 3 feet clear of anything that can burn, and never near gasoline, paint thinner or solvents.^[8]

The Big Buddy burns propane right in the garage, with no vent to the outside, so it uses the air you breathe. Its manual sets these rules.^[2]

1. Give it fresh air. Crack the garage door or a window at the top and the bottom.“This heater requires a vent area of 18 square inches (example 4.25” x 4.25” opening) at the ceiling and at floor level for adequate ventilation during operation.”
2. Put a carbon monoxide alarm in the garage. Its low-oxygen shutoff is a backup, not a reason to close the garage up. The CPSC says: "CO alarms should be placed on every level of the home and outside sleeping areas." Put one in the garage too.“When used without adequate combustion and ventilation air, heater may give off excessive CARBON MONOXIDE, an odorless, poisonous gas.”
3. Stay with it. Turn it off when you leave the garage.“Never leave the heater unattended while burning. Never operate the heater while sleeping.”
4. Keep it clear. Its manual asks for 30 inches of space above it, 24 inches in front and 6 inches at the sides. Keep it away from gas cans and solvent fumes.
5. Store the tank outside. Unhook the cylinder before you bring the heater inside.“Cylinders must be stored outdoors out of the reach of children and must not be stored in a building, garage or any other enclosed area.”
6. Never use an outdoor-only propane heater indoors. A forced-air propane "torpedo" heater made for job sites is not made for a closed garage. Only use a model its maker approves for indoor use, like the Big Buddy, and follow its manual.

All 5 garage heaters in stock that pass our safety screen: heat, plug, safety mark and Amazon price

Heater	Heat	Power	Safety mark	Price	Buy
Electric: 240 V, need their own circuit
CTSC MGH1056-02 5,600 W garage heater	5,600 W	240 V · 6-30P plug	UL	$143.99	Buy
CTSC MGH1085-02 8,500 W garage heater	8,500 W	240 V · hardwired	UL	$161.99	Buy
CTSC MGH10100-02 10,000 W garage heater	10,000 W	240 V · hardwired	UL	$269.99	Buy
Comfort Zone CZ260ERBK 10,000 W garage heatersold by Amazon	10,000 W	240 V · hardwired	ETL	$319.09	Buy
NewAir NGH1K6WH00 10,000 W garage heatersold by Amazon	10,000 W	240 V · hardwired	ETL	$389.99	Buy
Propane: no wiring, needs fresh air

Electric heaters here state a thermostat, an overheat cut-out and a UL, ETL or CSA mark in their own listing. Propane: the Big Buddy MH18B, which its manual says is certified to ANSI Z21.103 for indoor and outdoor use. Recalled models are left out. Prices read live November 4, 2026.

What is the best garage heater?

For a cold, drafty or large 2-car garage, the Comfort Zone CZ260ERBK 10,000 W garage heater ($319.09 on Amazon on November 4, 2026). It makes 10,000 W on 240 volts. For an insulated 2-car garage a 5,000 W heater is the right size, but none that Amazon.com sells states every safety feature on our screen today.

What size heater do I need for a 2-car garage?

About 4,000 to 5,000 watts (13,648 to 17,060 Btu an hour) for an insulated 2-car garage of 400 to 500 sq ft, at 10 watts per square foot. If it has no insulation or your winters are cold, go to 7,500 to 10,000 W.

Is propane or electric cheaper to heat a garage?

Delivered propane is cheaper per unit of heat: about $2.94 per 100,000 Btu at the U.S. average, against $5.33 for electricity. But 1 lb cylinders cost much more an hour on high. An electric heater has no fumes and can run on a thermostat all day.

Is natural gas cheaper than electric for a garage heater?

Yes, per unit of heat: about $1.85 per 100,000 Btu delivered by an 80% efficient unit, against $5.33 for electric. A gas unit heater needs a gas line, a vent and a pro to install it.

Is a Mr. Heater Big Buddy safe in a garage?

Its maker says it is approved for indoor use, except in Massachusetts and Canada, and it shuts off if oxygen runs low or it tips over. Its manual still asks for an 18-square-inch opening at the ceiling and the floor, says never to leave it unattended or use it while you sleep, and says to store the propane tank outside. Add a carbon monoxide alarm.

Can I plug a garage heater into a regular outlet?

Only a 1,500 W heater, which warms the spot you work in, not the garage. A heater big enough for the whole garage needs a 240 V circuit, either hardwired or a 240 V outlet.

How much does it cost to run a garage heater?

A 5,000 W heater costs about 91¢ an hour on high at the U.S. average electricity price, or $3.64 for a 4-hour session. A 10,000 W heater costs twice that. Prices vary a lot by state.

Do I need an electrician to install a garage heater?

For a 240 V heater, yes, unless you wire 240 V circuits yourself. A hardwired heater connects straight to the panel, and a plug-in one needs a 240 V outlet on its own circuit.

• Best space heaters for a bedroom, bathroom and garage
• Best space heater for a large room (400 sq ft)
• Best mini split for a garage
• What a space heater costs to run in your state
• The most energy-efficient space heater

1. 1

   Amazon listings: watts, plug, safety marks and room claims as each listing states them

   5 electric garage heaters and 0 propane listings, from each listing's own words; price, seller and stock read live November 4, 2026.

2. 2

   Mr. Heater: Portable Big Buddy Radiant Heater, Model MH18B, Operating Instructions and Owner's Manual (78435 Rev A)

   Read October 22, 2026. Indoor use, ventilation, run time per cylinder, clearances and storage.

3. 3

   U.S. EIA: British thermal units (1 kWh = 3,412 Btu)

   So 1,500 W = 5,118 Btu an hour.

4. 4

   U.S. EIA: average home electricity price

   U.S. average 18.19¢ per kWh, Year-to-Date through July 2026. Same figure as our space heater cost page.

5. 5

   U.S. EIA: weekly U.S. propane residential price

   $2.689 a gallon, week of October 19, 2026. EIA: 1 gallon of propane = 91,452 Btu.

6. 6

   U.S. EIA: residential natural gas price, annual

   $15.34 per thousand cubic feet, U.S. average, 2025 annual average. EIA: about 1,037 Btu per cubic foot (eia.gov/tools/faqs/faq.php?id=45).

7. 7

   Dimplex (heater maker): "How big a heater do I need to heat my room?"

   "The general rule for electric heat is to use 10 watts of heat per square foot of space ... in a standard insulated room."

8. 8

   U.S. CPSC news release, January 23, 2026: Keep warm and safe this winter (generators, furnaces and space heaters)

   Read October 17, 2026. Portable heaters, including electric space heaters: an average of 1,600 fires, 70 deaths and 150 injuries a year (2020 to 2022). 3 feet from drapes, furniture and bedding; plug directly into a wall outlet, never an extension cord or power strip; "Turn off heaters when sleeping."

9. 9

   U.S. DOE Energy Saver: Electric Resistance Heating (archived copy, January 1, 2026)

   "Electric resistance heating is 100% energy efficient in the sense that all the incoming electric energy is converted to heat." Heat pumps "easily cut electricity use by 50%" compared with it.

10. 10

    ChatGPT answers to "best garage heater" (3 runs, October 24, 2026)

    The models it named, matched to Amazon listings by model number only.