How to Use an Electrical Box Extender

Updated: Sep. 18, 2023

Don't put up with an unsafe, unsightly electrical box installation. You can easily fix the problem by installing an electrical box extender.

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20 minutes






Do you have a receptacle that seems loose, or is set back too far in the faceplate? Or maybe you're considering adding a backsplash, but you're not sure how to move the electrical devices out to accommodate the tile. The remedy in both cases? An electrical box extender.

Box extenders are inexpensive, easy to install and — best of all — they bring your electrical installation up to code. Flush-mounted devices like receptacles and switches can only have a 1/4-inch gap between the front of the electrical box and the finished wall. If you add a layer of drywall, put up shiplap or install tile, you'll go over this limit.

Here's how to install an electrical box extender.

Tools Required

  • Flat-head screwdriver
  • Level
  • Non-contact voltage tester
  • Phillips screwdriver or drill with Phillips bit
  • Wire strippers (optional)

Materials Required

  • Electrical box extender
  • Electrical wire (optional)
  • Wago lever nuts (optional)

Project step-by-step (5)

Step 1

Turn off power

  • Turn off power to the receptacle at the breaker.
  • Test with a non-contact voltage tester to verify the power is off.
    • If the tester beeps, do not proceed until you figure out which breaker controls the receptacle.

Box Extender Loose Receptacle Ally ChildressAlly Childress for Family Handyman

Step 2

Remove faceplate

  • Remove the faceplate by unscrewing the small screw(s) holding it in place.
  • Run the voltage tester along the sides of the receptacle to ensure the power is off.

Box Extender Gap Between Strap And Box Ally ChildressAlly Childress for Family Handyman

Step 3

Detach existing receptacle

  • Remove two 6-32 screws holding the receptacle to the existing box.
  • Gently pull the mounting straps to extract the receptacle from the box.
  • Stick your tester deep into the box to check any additional wires for power.
    • Find and turn off any additional breakers if tester beeps.

Box Extender Test Before Removing Ally ChildressAlly Childress for Family Handyman

Step 4

Add box extender

  • Leave the receptacle wired, if wires are long enough to extend out to new position.
  • Slide the receptacle through box extender and push the extender into electrical box.
  • Insert provided 6-32 screws through the device mounting strap and box extender.
    • These will be longer than the ones you took off, to accommodate the extender.
  • Level as you screw the receptacle and extender into the electrical box.

Box Extender And Screws Ally ChildressAlly Childress for Family Handyman

Step 5


  • Reattach the faceplate.
  • Turn on the breaker.
  • Verify the receptacle works.

Box Extender Turn Off Or On Breaker Ally ChildressAlly Childress for Family Handyman