Using a Space Heater This Winter? The 3-Foot Rule and More

Keep anything that can burn at least three feet from a space heater. That one line shows up in advice from the U.S. Fire Administration (USFA) and the National Fire Protection Association (NFPA), and it is the rule most worth remembering. The NFPA also says that half of home heating fires are reported in December, January and February, so the cold months are when the rule matters most.

A space heater doesn't need to be new to be safe, but it does need a clear three feet around it and a wall socket to itself.

If you are thinking about buying a heater this season, or pulling one out of storage, here is the short version of what the fire agencies say.

Why portable heaters get special attention

An older USFA study, published in 2001 and based on 1996 to 1998 data, found that portable heaters accounted for only 10% of home heating fires but 30% of the injuries and 40% of the deaths from heating fires. The same report named the bedroom as the leading place these fires start, and said fabric and wood or paper made up 59% of the materials ignited. It also said placing things too close to a heater is a major problem, and that January and February were the peak months.

That data is old, so I am not offering it as today's totals. I include it because the pattern it describes, a small share of fires with a large share of harm, is why every agency repeats the same few rules.

The rules in one table

The NFPA adds that all fuel-burning equipment should be vented to the outside to avoid carbon monoxide poisoning, and that carbon monoxide alarms should be installed and maintained. If you smell gas from a gas heater, do not light it. Leave the home and call the fire department or gas company.

Checking a used heater

None of the agency pages I opened give a checklist for used heaters, so the following is my own, built on their rules:

1. Inspect the cord and plug. The USFA tells you to check for cracks and damage. A frayed cord is a reason to walk away.
2. Look at the housing. Cracks, melted spots or scorch marks suggest a past problem.
3. Make sure the controls turn on and off smoothly.
4. Ask whether it shuts off if it tips over. Many modern heaters have this feature. I have not verified a standard, so ask the seller and read the label.
5. Confirm what fuel it uses. The NFPA says to use the type of fuel the maker specifies for fuel-burning heaters.
6. Read the manual or find it online so you know how to run it correctly.
7. Run a recall check using our five-minute guide.

If the heater only has a little dust in its grille, a gentle clean may be enough. If it smells burnt when you test it, pass.

Where to put it at home

• On a hard, flat floor, not on a stack of boxes or on a bed.
• Away from curtains, bedding, sofas and clothes, with that three-foot clearance.
• With its own wall outlet. No power strip.
• Where children and pets cannot bump it.
• Off when you leave the room or fall asleep.

Many people want a heater for a bedroom, which is exactly where the USFA's older study found most portable heater fires begin. That is a reason to be strict in that room.

Saving money on heat in the DC area

Winters in DC, Maryland and Virginia are cold enough to make people reach for a space heater, and energy costs are rising: federal data put energy prices up 16.3% in the 12 months to August 2026, as we covered in what is cheaper and what is not. A heater can warm one room more cheaply than the whole house, but only if it is used safely. Browse Buy Now for what is in stock, read the help page for how pickup works, and always inspect before you pay.

The bottom line

Three feet of clear space, a wall outlet of its own, a solid floor and off when you leave. Check a used heater's cord and housing, ask about the tip-over shutoff, and test your smoke alarms every month. Those are the rules the fire agencies keep repeating because they work.

If a friend is bringing a heater down from the attic this week, send them this first.