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What Size Screws for Electrical Outlet Box? (Answered)

Screws are very essential elements when it comes to electrical wiring and fitting. Screws can be needed for any type of electrical work. Screws Are mostly used in electrical boxes and outlets and switches.

In this article, we will be discussing the screws that are needed for an electrical outlet box to fit in the wall.

What size screws for electrical outlet box? 

6-32 and 8-32, are the most common screw sizes that are required to use in electrical boxes. In addition to that, it is recommended to get rounded or hex head screws inside the box for a better fit. These screws are useful when mounting the electrical outlet boxes into thicker surfaces. 

People who do the electrical works in their households need different sizes of screws in their walls to fit electrical outlet boxes, ceiling outlet boxes, exterior outlet boxes, junction boxes, etc. These screws are usually about 1 inch in length.

You can easily screw them into any type of wall and mount the electrical boxes. Moreover, some screws require wall plugs when mounting the electric boxes. Wall plugs usually.

Hold the screws inside the wall in case the plaster breaks down and makes the screw loosen up. So, there are different sizes of screws needed for different types of electrical outlet boxes.

Some of the electrical outlet boxes which need different size screws are described below: 

Screws for standard electrical outlet box:

Most of the electrical outlet boxes nowadays require a modern type of screws that is 6-32 Flathead screw. In case you are using this proof for a heavy type of electrical application, an 8-32 screw will be ideal.

If you find the 6-32 screws noticeably smaller, then you can go for the 10-32 ground screws and they must be painted visibly green. 

Screws for ceiling outlet boxes:

Flat-headed and zinc-coated screws are best for electrical application. In addition to that, if you can use a stainless steel-made screw along with it, then it will keep the electrical box in good condition as well as safe. 

Screws for exterior outlet boxes:

Exterior outlet boxes require a 6-32 x 1-1/2-inch Flathead machine screw. However, Flathead refers to the shape of the screw head. It can easily fasten with a screwdriver.

You can use nuts along with it to prevent the overturning of the screw. 

Screw size for junction boxes:

The junction boxes generally require a heavy-duty screw. Which can be an 8-32 or even 10-32. Since the junction boxes hold more weight, for example, they hold light fixtures.

So, 8-32 IS. Ideal to use for junction boxes. Or you can use the 10-32 screws if there are no alternatives.

Electrical box ground screw size:

When discussing the electrical box ground screw sizes, you can simply rely on 10-32 screws as the ideal size for the ground screws. It is highly recommended to use round head screws.

Because oval head or flathead screws won’t make very good contact with the wire. As a result, the application for the electrical ground screws will be of no use.

What size screws to use for an electrical outlet cover?

Since there are specially designed slots inside the electrical outlet cover to fit the screws in it, you can decide whether you need that exact design to screw for the outlet cover.

The screws that are considered standard to use in electrical outlet cover are 6-32 screws. They are available in different sizes in the market. The most common sizes of these electrical outlet cover screws are 5/16 inches and half inches.

And 1/2-inch screws are more likely to fit in any electrical outlet covers. The length of the screws may vary. Even if you have extra space in between the wall and the electric outlet cover, you might need longer screws.

What size screws to use for an extended Outlet box? 

Using the proper sized screw for your outlet box is important because that ensures the proper flow of the electrical application. An extended outlet box is considered when there is a large gap between the wall and the outlet cover.

So, you will need longer screws to cover the whole outlet box and mount it to the wall. For this, you might choose 8-32 screws or 10-32 screws that are specially made for heavy ceiling outlet boxes.

But they can be also used to join the boxes that have a huge gap between the walls. So, make sure when you buy one, get the accurately sized one so that it fits in the slots properly.

What type of screws are used for an electrical outlet?

Nowadays, there are a wide variety of electrical screws that are at every level in the market. You need to choose the screws based on their size, length, and the number of threads in a screw.

Getting the right screws for the application is difficult because there might be a huge gap between the electrical cover slot and the surface. Sometimes the surface is so thick that you need to drill much deeper to place the screw properly.

Generally, receptacle screws are used when it comes to electrical applications in households. If there is a panel surface, long screws become useful as there are thick surfaces on which you’re mounting the outlet box.

Just in case you might need extra-long screws if you have pulled the electrical outlet cover forward. There are different types of screws required for different types of electrical applications.

The following is a discussion of what type of screws are used for an electrical outlet.They are mentioned below: 

5/16-Inch 6-32 thread screws:

These 5/16 inches long, 6-32 threaded screws will allow you to execute smaller electrical applications in your households. They are also very available in the market and have color machine replacement screws. 

6-32 x 1″ flat head machine screw:

These flathead screws are ideal to use in electrical box switches and outlets. These screws come with extra nuts so you can see the other side of the screw using nuts when you are done with the drilling.

6-32 x 1-1/2″ screw: 

These Flathead machine screws can be used in extended outlet screws. These are the longest screws to use in outlets and boxes, 1-1/2″ will be the maximum length you will ever need in a typical electrical operation.

What are electrical screws made of? 

Typically, there are many different types of materials used when manufacturing the screws. The screws are made of stainless steel with an additional layer of zinc coating to prevent unwanted corrosion and extend its lifespan.

In addition to that, brass, aluminum, black, nickel and zinc plated Chrome is also used to manufacture the screws in case there are no alternatives to using zinc plating.

These screws not only extend the lifespan of the screws but also help to stick to the surface very strong and due to long-term use, they won’t come off from the wall.

How to measure screw size from hole? 

Measuring the screw with the same size of the hole is important because sometimes if you drill the hole deeper or if you have smaller screws, your screws might not fit well with the surface.

There is also a chance of the screws coming out unexpectedly. Make sure to measure the depth of the hole and measure the length of the screws. Here are some tips by following which you can easily measure the size of the screws: 

Measure this crew from the tip: 

After you have drilled the surface, you can measure the screw length from the tip, and match it with the depth that your drill bit has gone into. This is the easy way to measure the right size of the screw.

Measure the diameter:

Measuring the right diameter is important because you might drill a narrow hole and in case your screw is very thick then you might face issues when screwing it inside the outlet box.

Distance of the threads:

The distance between the threads in a typical screw is 1mm. But still, you might need to measure it to place the screw properly.

Where can I buy electrical screws?

The screws are not very difficult to find out. If you are looking for the typical standard screws, you can get them at the local grocery stores.

And just in case you don’t know which one will be the perfect screw for the electrical outlet box, you can simply go to the local hardware shops and consult with the technician over there about the rights screw.

Although in most cases the 6-32, 8-32 and 10-32 screws can be found in every hardware store around you.

Final thoughts 

For the regular typical electrical operations, you can use the 6-32 screws. So, 1 inched size screws are ideal for mounting electrical outlet boxes. Although 6-32 is too light for any type of electrical work, you can use an 8-32 or a maximum of 10-32 sized screws instead.