Running a Space Heater vs a Furnace: Costs Compared


Are you having a hard time comparing space heaters vs furnaces?

Don’t worry, this is a common issue. Luckily, you’ve come to the right place for answers.

If you’re looking to stay warm without breaking the bank, understanding the differences between space heaters and furnaces is a must.

When comparing space heaters vs furnaces, you need to consider the number of rooms you need to heat. While space heaters have a lower upfront cost and are ideal for heating a single room, furnaces are more economical when heating multiple rooms at the same time.

Keep reading to learn more about the main differences between furnaces vs space heaters!

Space Heaters vs Furnaces

A space heater is great for heating a room quickly. And if the room is relatively small, you won’t have to have a space heater on very high to feel the benefits.

A furnace is an excellent source of steady heat. It heats rooms evenly and gradually. The heat is so effective that you can still feel the benefits of a furnace after you turn it off.

But here comes the million-dollar question. Space heater or furnace, which is best for your home?

Take a look at the upcoming information that will compare the two in the most important categories. These are – upfront cost, running cost, and practicality.

#1 Upfront Cost

To start the ball rolling, let’s see how much both space heaters and furnaces cost upfront.

The average price paid for a space heater is $60.

But that said, you can pick up a simple space heater for as little as $25. True, a $25 model won’t heat a mansion. But it will take the chill off your feet in the winter and warm up a small office space.

You can also choose a space heater that is a lot more expensive. You can pay up to $2000 or even more for a really swanky heater with all the features. And they hold their heat a lot better than your bog-standard space heater.

Here’s what you can expect from a more expensive model.

  • Automatic shut-off feature when the appliance gets too hot
  • Varying temperature positions
  • Constant temperature function
  • Radiator-style design rather than a fan style
  • Tip-over protection

But what about a furnace? When it comes to a furnace, you should expect a whole different price range. Their basic starting prices are hundreds of dollars. And if you buy a really nice furnace for your home, you can expect to shell out thousands.

If your choice is based on the initial price, you should choose a space heater. Space heaters have the most economic upfront cost.

Space heater in living room
Space heaters have the lowest initial cost

#2 Running Cost

Now we all know that the initial cost of an electrical item is not often the price that hurts. It’s the running cost that we are really interested in.

So how much will it cost you to run a space heater in the long term?

The running cost of your space heater depends on the following factors.

  • Your electricity rate per kW
  • The size of your space heater
  • How many hours per day you will run the space heater
  • The temperature you will have the space heater set to

As you can see, the price can vary depending on a few factors. But let’s talk averages. A 1,500W heater (the average size space heater) costs around $0.20 per hour. If you were to run it for 12 hours a day on high, it would cost you $2.40 per day or $72.00 a month.

Every home is different. To work out the cost of running a space heater in your home, take a look at our easy-to-use calculator.

What about a furnace? The running cost of a furnace is also dependent on a few factors. Here are some of them.

  • Your gas or electric tariff
  • How many hours a day you will run the furnace
  • The temperature you will have the furnace set to

One of the biggest game-changers when it comes to furnaces is the type of furnace you have. Gas furnaces run on average 63% cheaper than their electrical counterparts. If you are running an electrical furnace, you can expect to pay a lot more. Choosing between gas and electric makes a massive difference in the price.

How does that reflect on the average price? The average price to operate an electric furnace is $7.30 per day, or $219 per month. However, the average price to run a gas furnace per day is $5 or $150 per month.

Now, that was a lot of information. Here’s a rundown of everything you need to know price-wise about space heaters and furnaces both gas and electric.

Space Heater Gas Furnace Electric Furnace
Price per day   $2.40   $5.00   $7.30  
Price per month $72.00 $150.00   $219.00  
Price per year $864.00 $1,800.00 $2,628.00

Looking at that, one could be persuaded to conclude that a space heater is the cheaper option. But that might not necessarily be the case. Here’s why.

  • The figures mentioned above indicate the price for using a space heater in just one room. If you are looking to heat more than one room, you will have to add that cost again for each additional room.
  • A furnace can heat multiple rooms. You do not need to add in an additional cost for more than one room.

So what is the real conclusion when it comes to running costs? A furnace is the cheaper option if you want to heat multiple rooms. If you want to heat only one room, a space heater will be the cheaper option.

Furnace panel
Any furnace is more economical when heating a whole home, compared to a small space heater.

#3 Practicality

Up until now, we’ve seen how space heaters and furnaces measure up when it comes to costs. But let’s talk practicality for a moment. How practical is it to use a space heater?

For a space heater to work efficiently, you will need to do the following.

  • Close the doors
  • Keep all drafts sealed
  • Keep the heater in one room
  • Maintain the heater on an intermittent setting to avoid overheating
  • Clear the space around the heater

And how practical is a furnace?

  • A furnace can be used to heat multiple rooms at once
  • It’s easier to control via one central thermostat
  • It takes up no additional space/outlets

So which is more practical? A furnace is more practical because it can heat multiple rooms at once, and it will not take up extra floor space in each room. You can also keep the doors inside the house open without suffering any loss of heat.

What about a space heater?

When you heat a room with a space heater, you will have to keep the door shut and keep any drafts well sealed. A space heater is less practical as it can only heat one room at a time.

You should also ensure that the heater remains upright at all times. You should bear in mind the loss of floor space when using a space heater. This can be inconvenient in apartments and small spaces.


So what can we conclude about the two? Which is better, running a space heater or a furnace?

You should choose a space heater if:

  • You are looking for a heater with the cheapest initial cost
  • You want to heat just one room in the house

You should just use your furnace if:

  • You want to heat more than one room at once
  • You are looking for an economical way to heat multiple rooms simultaneously
  • You want to heat multiple rooms without losing too much floor space

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Have a great day!


I've been helping homeowners with appliance repair since 2016. Starting out as an enthusiastic amateur, I've since worked with many Appliance, HVAC, and DIY experts over the last 7+ years. My mission is to help fix your appliances and prevent future issues - saving you stress, time, and money. Visit my author page to learn more! Read more