The outlet is full, the room is cold, and a power strip looks like the easiest fix. But some of the things you should never plug into a power strip are exactly what people reach for as the weather cools, starting with the space heater. Ordinary household power strips are meant for low-current equipment such as computers and chargers, not as a workaround for space heaters or major appliances. Here are six things to keep off a power strip, plus the warning signs that mean it is time to stop using an outlet.
The short answer: plug space heaters, refrigerators, freezers, microwaves, air conditioners, coffee makers and toasters directly into a wall outlet, and never plug one power strip into another. Fire officials and university safety offices say to use strips only for a few low-current devices, and to follow each appliance’s manual.
Six things you should never plug into a power strip
1Space heaters
The Consumer Product Safety Commission says in its 2026 winter safety release: “Plug electric space heaters directly into a wall outlet, never into an extension cord or power strip.” It reports that portable heaters, including electric space heaters, are involved in an average of 1,600 fires a year, with 70 deaths and 150 injuries annually from 2020 to 2022. The Washington State Fire Marshal’s Office gives the same direct-to-wall instruction in its heating safety release and also advises against plugging other devices into the same outlet or circuit as a space heater.
Do this: plug the heater directly into a properly working wall outlet, avoid running other heavy appliances on the same circuit and follow the manufacturer’s instructions.
2Refrigerators and freezers
USFA’s electrical appliance fire safety card says to always plug major appliances, including refrigerators, stoves, washers and dryers, directly into a wall outlet, and never to use an extension cord with a major appliance because it can overheat and start a fire. The University of Nebraska Medical Center’s power strip guidance says not to plug major appliances such as microwaves or refrigerators into power strips. A strip can also be switched off or knocked loose, which could leave food unprotected. That last point is our own observation.
Do this: plug refrigerators and freezers directly into a wall outlet and follow the manufacturer’s instructions. If the outlet is loose, damaged or too far away, have an electrician fix it.
3Microwaves
The UNMC guidance names microwaves alongside refrigerators as major appliances that do not belong on power strips. A University of Kansas environmental health and safety handout lists microwave ovens among the devices that power strips are not designed for.
Do this: give the microwave its own wall outlet rather than sharing a strip with other kitchen gadgets.
4Air conditioners
UNMC says heavy-draw equipment such as heaters and air conditioners does not belong on a power strip. The Massachusetts Department of Fire Services electrical fire
