Standard screws for toggle, duplex and blank plates are 1/2" in length.
If your box is recessed into the wall you can buy longer screws.
Rocker switch plates and some other specialty wall plates have 5/16" screws because longer screws will hit the wall surface underneath the plate.
Looking for a switch plate with screws spaced a certain length apart? Find the most common screw size placements plus solutions for unusual installations.
Screw to Edge of Plate Dimensions
Since there are so many sizes of plate - standard, oversize, wide, narrow, etc. - the distance from the screw hole to the edge of the plate can vary.
If you have limited space surrounding your outlet or switch, you'll want to verify the plate's measurements will work in your application.
Here are the measurements from the center of the screw hole to the edge of the plate on several switch plate sizes:
Standard Switch Plate
Tall Switch Plates
Oversize Wall Plates
1.5 Inch Narrow Switch Covers
Under 2 Inch Narrow Switch Covers
2 Inch Wide Cover Plates
2.25 Inch Covers
2.5 Inch Narrow Faceplates
1 Gang Half Narrow Covers
2 Gang Half Trimmed Covers
3 Gang Half Narrow Plates
4 Gang Half Thin Plates
Screw Sizes & Types
Standard slotted screws are known as 6-32 oval head screws. They feature a slot in a slightly rounded top (except for specialty screws) and come in a wide variety of lengths.
The two most common sizes of wall plate screws are 5/16” and 1/2”. Why aren’t they the same?
Screw size varies depending upon the device and placement of the openings. Screw lengths include 5/16" (.31") , 1/2" (.5"), 3/4" (.75" specialty size), 1" (1.0") 1-1/2" (1.5"), and 2" (2.0"). Note that traditionally, the shortest screw was .25" long but the default is now 5/16".
For certain applications, unique screws with unusual heads are used to hinder the removal of the screws. These tamperproof screws require specialty screwdrivers for installation or removal.
Buy Spanner screws.
Screw Spread Length
First, The Basics
The length of the spacing between screw hole positions on a switch plate is dependent upon the device opening. This spread is consistent no matter where the opening is on a plate. Below are all the standard screw placements and the types of switch plates with which they are used.
Center-to-Center Spacing - Screw hole spread is measured from the center of one opening to the center of the other (top to bottom on a vertically oriented cover; the distance between each screw left to right on a multiple-gang plate is a standard 1-13/16"). On switch plates, the opening has a tapered recess to allow room for surface of a 6/32 domed screw to sit flush with the surface. The actual opening at the bottom of this taper is only 3/16" across even though the recessed area is about 5/16" in diameter.
Screw Spread Remains Constant - Note that screw spread does not change on oversized or narrow plates - it remains a standard measurement no matter the size of the cover plate. On multiple-gang switch plates, the width between devices (left to right) will be 1-13/16".
Screw Openings Match the Device - The placement of the screw hole is determined by the device that will be placed in that particular position.
Interchangeable, Block or Strap Mount - 3.812" or 3-13/16" - Wall plates with this dimension include Decora rocker covers, Despard switch plates, and many low voltage wall plates. The wall plate screws included for these openings are 1/4" to 5/16" long. The short 1/4" length was the traditional choice so they would not run into the electrical box or wall surface behind the screws holes, however the newer 5/16" length is now preferred because it offers a little extra length for gripping the box. Use the 1/4" screws for situations where there is very little clearance behind the device strap such as when using with a mudring.
With strap mounting, plate is screwed into the far ends of the device straps. Because these straps are typically sitting close to or directly on the wall behind the straps, screws are kept short at 1/4” to 5/16” in length.
Image shows top view of electrical box with Decora rocker switch and cover plate.
Large Ceiling Box Mount - 3.5" or 3-1/2" - This spacing is used on round cover plates for larger (4") round or octagonal ceiling boxes. Shop for Round Ceiling Box Cover Plates. Standard screws - 1/2" long.
Box Mount - 3.281" or 3-9/32" - This is the spacing used for mounting on a standard electrical box. This is typical for blank or louvered wallplates, and phone or cable covers. Standard size screws provided are 1/2" long.
Box mounting has 3.218” spread & installs into the junction box. Regular 1/2" screws are standard.
Image shows side view of blank plate being screwed directly into electrical box tab.
Small Ceiling Box Mount - 2.75" or 2-3/4" - This spacing is used on small (3.25") round or octagonal ceiling boxes. These plates are typically circular. Shop small ceiling box covers. Standard length 1/2" switchplate screws included.
Device Mount - 2.38" or 2-3/8" - For this spacing, the device is mounted into the electrical box and the plate actually screws into the electrical device strap or housing. Found on toggle wall plates and single 1.4" outlet covers. Regular ½” screws are standard & provided with device mount plates.
Device mount installation - image shows side view of toggle light switch & cover installation.
Center Mount - Typically used on standard duplex outlet plates or round ceiling blankup covers when mounting pendant lights or other lighting fixtures. Available with flat, domed, and deep versions. Standard length screws included are 3/8" long. Extra long outlet screws available.
Center mount plates installs with a single screw in the center of the electrical device. Regular ½” screws are standard for duplex plates, 1” are standard for circular plates that must use a mounting strap.
Image shows how cover is screwed into center of duplex outlet.
Some specialty covers have odd screw spacing, such as this vintage phone jack cover with a 1-7/8" screw spread.
Some outdoor wall boxes need covers with larger spacing, like this plate with 5.25" between screw openings.
The largest screw spacing we cary is 6.625" apart.
These plates cover boxes for doorbell intercom speakers that are no longer in use.
No Screw Holes - No hole wall plates are the preferred choice when you have a custom application such as oddly spaced screws, whether with a unique spread or for an out-of-center placement on a limited number of plates. This gives you maximum flexibility in designing a layout up against beams or cabinetry or when needing a cover for customized equipment. Drill your own holes or have an opening cut at a machine shop. Many sizes available on the blank wall plate cover page. No screws are included with these plates and must be ordered separately. Buy the standard wall switch plate screw size or long switch plate screws if needed. Note: this no-hole switchplate is not the same as a "screwless" wall plate (below).
Screwless Wall Plates - Screw-less light switch covers in fact require two separate plates - one with screw holes and a snap-on overlay without, and hence are generally more expensive. The edges typically have a 90 degree return (sharp square edges) rather than a more user-friendly 45 degree beveled edge.
Shop screw-free covers here. Available in a variety of sizes with rocker openings which can be converted with inserts available for purchase here.
See how devices, cover plates and electrical box screw holes align when you read about Screw Hole Spacing on Electrical Device Covers
If you need unusually configured screw openings on a switchplate and and need them in quantity your best bet may be to have your wall plate covers custom made. Please contact us.
Next: Get help with industry terms - read our Switch Plate & Device Terminology article.