A Comprehensive Buyers Guide for Space Heaters

Ile Kauppila

Written By

Ile Kauppila

Fact Checked By

Josh Mitchell

Last Updated On

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Key Takeaways

  • Space heaters are differentiated in terms of the heating capacity, the fuel type they use, their heating method and and their physical size.
  • Heating capacity for electric heaters is measured in watts. For gas heaters, BTU is used. 
  • Depending upon the type of heater and the features it has, the price range can vary drastically.

Deciding on a space heater can be tricky. There are so many options on the market, each claiming to be the best.

That's why it's so important to consider your needs regarding room size, safety, and efficiency before you buy.

In this comprehensive space heater buying guide, I’ll cover everything you need to know before deciding on a great space heater for your home.

What Defines a Space Heater?

Just as the name suggests, a “space heater” is a device that’s designed to heat up a specific amount of space.

Compared to central heating, portable space heaters are better equipped for small spaces rather than entire homes, like bedrooms, offices, bathrooms, and living rooms.

Even though they all focus on the same function, there are many different types of space heaters ranging in heating capacity, aesthetics, safety features, and power source.[1]

Main Considerations Before Buying A Space Heater

Living in a cold environment, I’ve had a lot of experience with space heaters.

Over time, I’ve come to realize that there’s no #1 option on the market.

That’s because every person’s needs are different, specifically when it comes to the size of the room you’re looking to heat.

The room size will ultimately determine the required BTU output for gas heaters and the watts for electric heaters.

What is the Size of The Room That Needs Heatings?

Aside from safety, room size is the most important consideration in this space heater buying guide.

Most space heaters are rated for specific square footage based on the wattage or BTU output.

Gas heaters typically use British Thermal Units as the form of measurement, or BTUs, while electric heating is measured in watts (W).

Room Size

(Square Feet)

Electric Heating


Gas Heating























As you can see, the required wattage, as well as the BTU output, increases as the room size increases.

If you still need clarification, don't worry - most space heater packaging provides very clear information on how much square footage the device can handle.

How Much Do You Want To Spend?

You can actually save money on utility costs by using a space heater and reducing your central heat usage.[2]

Space heaters use less energy and are more cost-effective than central heating systems.

This is why so many people pull their heaters out of storage as the colder months approach - myself included!

Important Consideration

The more efficient a space heater is, the higher would be price tag typically.

Don't worry; you'll end up saving on energy costs in the long run if you use your heater wisely.

You can expect to pay about $0.20 per hour for a standard 1500-watt heater.

TL;DR: The first step in choosing a space heater is to determine the room size that requires heating and then decide on your budget and the features you require.

Factors to Consider When Choosing The Best Space Heater For Yourself

Aside from room size and upfront cost, there's a lot more to think about when it comes to buying a full room or personal heater.

Here's a complete list of the important considerations and questions to ask yourself before you buy:

Which Heater Type Do You Prefer?

There are several types of space heaters to choose from. Most companies label each type of heater based on the fuel type:

  • Natural Gas
  • Propane
  • Electric
  • Kerosene

However, you’ll definitely notice some other words used to describe heater type, like portable, personal, full-room, or outdoor.

Do You Need an Indoor or Outdoor Unit?

Thanks to outdoor space heaters, you don't have to confine yourself to the inside of your home this winter.

Outdoor heaters are great for heating up a small patio or yard so you can enjoy the winter scenery front and center.

Outdoor heaters typically use gas to power the heating element. There are two common types, including:

  • Liquid propane heaters:
    Outdoor heaters using propane are generally ground-mounted. They're great for keeping a small group of people warm. This is the ideal choice for a small patio or backyard.
  • Wall-mounted heaters:
    If you have some space on the exterior of your home, a wall-mounted heater might be the best choice. Just know that this typically requires professional installation since it’s directly connected to the gas line.

Do You Need a Personal or Room Heater?

Personal heaters, or portable electric heaters, are small and compact, typically used on a table or desktop.

Many people use this type of space heater in small bathrooms - it plugs into the wall and can be used directly on the bathroom countertop.

A room heater is much larger, and the size will vary based on the square footage it’s rated for.

They’re typically box-like in shape, but you can also find tower-style devices that oscillate while heating the room.

Deciding between a personal heater and a room heater is fairly simple.

If you want to feel warm and cozy at your desk while you work, then go with a personal heater.

If you need to heat a room in a short amount of time, a full-room heater is the better choice.

Is Electric or Gas Heater More Convenient For You?

Most indoor heaters use electricity as their power source. 

Once the device is plugged in and turned on, hot air is created by heated electric coils.

This hot air is then expelled into the room by a blower or fan, and depending on the size, it can be quite powerful. 

Because they require a direct gas line connection, gas heaters using natural gas or propane aren’t nearly as common for indoor use.

However, gas heaters are extremely powerful when it comes to heating, and they work fast to heat a large room.

There are pros and cons to both electric and gas energy sources.

Electric space heaters are much more convenient, and they don't require special venting or professional installation.

They come in many forms, including infrared heaters, convection heaters, panel heaters, and radiator heaters.

  • Infrared space heaters (radiant heaters):
    Infrared heaters provide direct heat to the specific areas in which they are pointed. They focus on spot heating, so while they’re not ideal for large rooms, infrared heaters can rapidly heat up a small space.
  • Convection space heaters:
    A convection heater uses the process of natural convection to circulate hot air around a room. Most models produce heat using convection technology, so you’re bound to come across many of these as you shop around.
  • Panel space heaters:
    Panel heaters use a combination of infrared and convection technology. Unlike a radiant heater, this type is great for evenly distributing warm air throughout an entire room.
  • Radiator space heaters:
    Most radiator heaters use the gas-powered method, but it's possible to find electric radiators as well that serve as a more permanent solution. Unlike radiator oil-filled heaters, there's no need to handle any flammable liquids with an electric radiator. These have a slim, portable design, making them ideal for small spaces.
Unfortunately, electric heaters aren’t quite as powerful as gas heaters.

Even though you’ll save energy in the long run, they typically cost more to operate, and you’ll see that on your electric bill.[3]

It’s also worth noting that kerosene and diesel-operated heaters are available.

These are typically only meant for outdoor use, but if you have proper venting, they can be used indoors as well if you don’t have direct access to gas or electricity.

TL;DR: The are many types of space heaters differentiated by fuel type they use, their heating output, physical size, indoor / outdoor usage, as well as by their mode of heating (i.e. radiant, convection etc.)

Understanding The Watts & The BTUs

Even if you try to avoid math at all costs, it’s still important to have some understanding of the energy units used to measure heating output for space heaters.

Before you decide on an indoor electric heater, pay close attention to the wattage that’s necessary to heat your specific area.

On average, space heaters use 1500 watts of electricity to operate, but it depends on the room size.

An average-sized room of 150 square feet requires about 1250 watts to heat, but a 300-square-foot room requires 2500 watts.

If you’re working in the BTU measurement, which is more common for gas heaters, there’s an easy way to convert watts to BTUs.

Simply multiply each required watt by 3.14; 1 watt is equivalent to 3.14 BTUs.

So for that 150-square foot room requiring 1250 watts, the BTU requirement would be 4262 (1250 x 3.14).

Important Consideration

Always use appropriately sized heaters for your room size to improve energy-efficiency and running costs. Larger heaters than necessary will consume excess power and smaller heaters than what is required will run for longer time to maintain heat. Both of which can add to your bill.

Take The Footprint Into Consideration

Room heaters come in all shapes and sizes. Space heater sizes vary from small, big, tall, short, fat, skinny - you name it.

Most space heaters require a good amount of space to safely operate, mainly because they should be clear from walls, furniture, fabric, and doorways.

That's why you should always check the footprint and compare it to your available space.

Although a large unit may be capable of heating an entire room, it won’t serve much purpose if there’s no available floor space to safely use the device!

Look For Energy-Efficient Certification To Save On Running Costs

One of the biggest reasons to use a space heater is to save on utility costs.

Central heating systems aren’t cheap to run, so supplementing yours with a space heater or two can seriously minimize costs.[4]

Just know that space heaters aren't designed to provide primary heat.

If you're living in a cold area, chances are you'll still need to use your central heating system.

But you won't have to crank the heat up as drastically if you're supplementing with space heaters.

Some space heaters are much more efficient and cost-friendly than others. To ensure that you’ll be saving on utilities, there are a few things to look for:

  • Opt for a newer model with the most updated features, and make sure that the heater comes with an Underwriter’s Laboratory (UL) label that proves proper procedures were used in the testing process.
  • Look for an Energy Star label; this certification is only given to the most energy-efficient devices.
  • Choose a heater with energy-saving features like programmable thermostat control, automatic shut-off, and a timer.
  • Buy a heater that makes sense for the room you're heating. An oversized heater will work quickly, but it will also use unnecessary energy.

TL;DR: Certification like UL and Energy Star help identify energy efficient models. Additionally look for feature like thermostat control for shutting off heater automatically.

Does It Come With Safety Features & Special Features?

If you look up statistics, you’ll see that there have been a lot of accidents from space heaters over the years.

Don’t let this stop you from buying one, though.

Important Consideration

Accidents relating to fire hazards and carbon monoxide poisoning typically only happen from improper, unsafe usage.

There are a few things to look for to ensure that a space heater is safe to use, including:

  • Automatic shut off:
    This feature automatically shuts off the device after long periods.
  • Overheat protection:
    Overheating protection means the heater will automatically shut off when the heating element gets too hot.
  • Programmable thermostats:
    Programmable features allow you to set desired temperature to avoid overheating to stay safe and save on energy costs.

Like most people, I’m a huge fan of special features, like multiple heat settings in addition to exact thermostat control.

With this feature, you can simply choose between high, medium, and low heat based on how much additional heat you need at that given time.

Many models now even come with Bluetooth operation and a compatible mobile app.

That means you can control exactly when direct heat is produced and play around with temperature settings without even being in the room.

TL;DR: Always look for safety features such as tip-over auto-shutoff and overheat protection to keep yourself and your surrounding safe.

What Is The Maximum Noise Level You Can Tolerate?

While your heater may be able to generate heat, chances are you won't want to use it if it's extremely noisy.

Electric space heaters are generally pretty quiet, especially those that use radiant heat.

The biggest source of noise for many heaters is the blower.

As hot air rises through the machine, the warm air is blown outwards into the room.

You’re likely to hear a slight whirring sound as the fan is blowing, but it shouldn’t be too much of a disturbance.

Many space heaters output anywhere from 30 to 56 decibels, typically falling somewhere in the low-40s.

To put things into perspective, your refrigerator outputs about 40 decibels.

Is It Aesthetically Pleasing?

While aesthetics aren’t the most important factor for buying a space heater - safety is #1! - it’s still something to think about.

You don’t want your heating source to be an eyesore sitting in the middle of your living room.

Luckily, there are plenty of heating options that are nice to look at, especially the newer portable heaters from brands like DeLonghi and Honeywell.

Popular Space Heater Brands

Now that you know what to look for when shopping around for natural gas space heaters, convection heaters, or radiant space heaters, the next step is to focus on the best heater brands.

You’ll come across dozens of highly-rated brands as you shop around, but in my experience, these are the ones you should be focusing on:

  • DeLonghi
  • Honeywell
  • Comfort Zone
  • Vornado
  • Heat Storm
  • Lasko
  • Dyson
  • Costway
  • Dreo

Are Space Heaters Really Safe To Use?

Space heaters are generally safe, but only if they’re used the right way.

Numerous house fires are started every year due to improper use of space heaters, so following safety protocols is a must.[5]

Here are a few helpful space heater safety tips to follow:

  • Only purchase space heaters with the qualified lab testing seal.
  • Keep the heater at least 3 feet away from anything that could potentially burn.
  • Only use a heater with a thermostat and overheat protection.
  • Never use an extension cord - wall outlets only!
  • Never use the same outlet for multiple large appliances.
  • Never leave your heater unattended.

TL;DR: Space heaters are very safe to use if proper safety precautions are taken and the manufacturer's safety guidelines are followed.

People Also Ask (FAQs)

How Much Does It Cost to Run a Space Heater?

Running a standard 1500-watt space heater costs an average of $0.24 for 1 hour of operation.

This is much cheaper than central heating, especially if you avoid using it during your electricity company's peak hours.

How Long Do Space Heaters Last On Average?

Like all appliances, space heaters have a specific life expectancy, and they should be replaced periodically.

In general, an electric space heater will last anywhere from 5 to 10 years, while a gas-powered model can last anywhere from 6 to 15 years.

How Long Do Space Heaters Last On Average?

The most efficient type of space heater is the sealed-combustion model. It operates efficiently because they do not draw warm air from the surrounding area.

Instead, they pull air from outside the home for the fuel-burning process before expelling it into the room.


  1. https://www.eia.gov/kids/energy-sources/natural-gas/
  2. https://www.imf.org/en/Publications/fandd/issues/Series/Back-to-Basics/Inflation
  3. https://www.forbes.com/home-improvement/hvac/gas-heater-vs-electric-heater/
  4. https://www.energy.gov/energysaver/small-space-heaters
  5. https://www.nfpa.org/-/media/Files/Public-Education/Resources/Safety-tip-sheets/PortableHeaterSafety.ashx

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Ile Kauppila

MA Multimedia Journalism / BA English Philology

Ile Kauppila
Ile Kauppila is a globetrotting writer and editor living in Virginia. Ile holds an MA degree in Multimedia Journalism and a BA in English Philology. Ile has written for a variety of home, HVAC, and energy-related websites and publications. He has covered HVAC solutions, insulation, and energy-efficient construction, automotive AC systems for multiple auto dealerships and garages.

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