Can you plug a power strip into an extension cord?
No. Plug a power strip straight into a wall outlet, not into an extension cord or another power strip. Plugging power strips or extension cords into each other is called daisy chaining, and it can cause an electrical fire.
What the listing, the tag and a strip’s manual say
UL calls power strips relocatable power taps, and its instructions for listed ones rule out plugging them into an extension cord or another strip.
The warning tag UL 817 calls for on extension cords says “Do not plug one extension cord into another.”
Tripp Lite’s manuals for its Power It! and PS-Series power strips say not to plug extension cords into the strip, and not to use it with 2-wire extension cords or adapters.
What to do instead
Use one extension cord long enough for the job, heavy enough for what’s plugged into it. See the extension cord gauge chart.
Don’t overload power strips and outlets.
Where you need more outlets than the wall has, an electrician can add an outlet.
Holiday lights
In a 2025 survey of 2,019 US adults by UL Standards & Engagement, more than half of holiday decorators (52%) admitted plugging multiple power strips or extension cords together to connect their lighted decorations.
Light sets made to plug into each other end to end are a different case. The set’s instructions give the limit for connecting them end to end. See how many light strings you can connect.
Overloading is the usual cause of an extension cord overheating. If any part of one is hot while in use, unplug it.
Common questions
Can I plug a surge protector into an extension cord?
No. Surge protectors are listed as power strips too, and the same instructions cover them.
Can I plug an extension cord into a power strip?
No, that's daisy chaining too, and Tripp Lite's power strip manual says not to plug extension cords into the strip. Plug the extension cord straight into a wall outlet, or use one cord long enough to reach.
The rules come from UL’s instructions for power strips and the extension cord warning tag (both quoted in OSHA letters), holiday safety advice from UL Standards & Engagement and UL Solutions, the CPSC, a light maker’s instruction sheet and a power strip maker’s manual. Checked against published data from OSHA, GE, CPSC, UL Standards & Engagement and UL Solutions (plus 1 more).
See all 7 sources
GE mini light set instructions, models 61515LO and 61516LO (Nicolas Holiday, 2025): set watts, end-to-end maximum, amps times 120, fuses, GFCI outlet outdoors
US Consumer Product Safety Commission, “Household Extension Cords Can Cause Fires” (Pub 5032): the rating on the tag, hot cords, at least 16 AWG, temporary use, cords marked for outdoor use, not through doorways
OSHA interpretation letter, September 28, 2015: the UL 817 extension cord warning tag
OSHA interpretation letter, November 18, 2002: relocatable power taps (power strips), surge suppressors and high power loads
UL Standards & Engagement, 2025 Holiday Safety Guide: daisy-chaining power strips and extension cords
UL Solutions, “Safe Lighting Tips to Keep the Season Bright” (2025): power strips and outlets
Tripp Lite owner's manuals: Power It! Power Strips (2022, 22-03-059 9341C5_RevA) and PS-Series Power Strips (2015, 933407; copies supplied by the owner, October 18, 2026): no surge protection, no extension cords into the strip, amp rating
General guidance from manufacturer and standards data. Products vary, so check the label and the maker's instructions.