How to Replace a Toilet Seat

If you are looking to replace a toilet seat I hope that this post is helpful. This isn’t the most exciting DIY project but it is a super easy one. With just a few common tools you can replace a toilet seat on your own with ease. The most common question is how determine the correct size. Here is everything that you would ever want to know about how to replace a toilet seat.

Toilet Seat Sizes

First thing that you are going to want to do is measure your toilet seat. Toilet seats are not universal so you will want to be sure to replace yours with one that fits the toilet bowl properly. The two common toilet seat shapes are round and elongated. Below is a picture of some of the toilet seats that they sell at my local Lowes store. On the left side of the picture you can see the elongated toilet seats (longer). On the right of the picture is the round shaped toilet seat.

If you don’t know which shape your toilet is, you can determine this by measuring the existing toilet seat.

Round toilet seats

Round toilet seats are typically 16.5″ from the center of the bolts to the front of the toilet seat

Elongated toilet seats

Elongated toilet seats are a little bit deeper and typically 18.5″ from the center of the bolts to the front of the toilet seat.

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How to measure a toilet seat

When it comes to replacing a toilet seat, the shape of the seat isn’t the only thing that you need to take into consideration. You’ll want to be sure to select a toilet seat that will fit the mounting holes on your toilet as well as the length and width of the toilet bowl.

Grab a tape measure and measure three distances to ensure that your new toilet seat will fit perfectly.

First is the distance between the center of the two mounting holes. The industry standard is 5 1/2″ but you’ll want to confirm the actual dimension on your toilet.

Second is the distance between the CENTER of the mounting holes and the front of the toilet. As discussed earlier, a round toilet will typically have a distance of 16.5″ and an elongated toilet will typically have a distance of 18.5″. If you notice that your toilet seat is a little off from the standard measurements one thing you might consider is purchasing a toilet seat that has front to back adjustability. This will give you a little wiggle room to adjust the toilet seat from front to back.

How to remove a toilet seat

Most toilet seats are installed with a screw that goes through the mounting holes that is secured with a nut. Depending on the manufacturer, this could be metal or plastic components so the specific tools required to remove your toilet seat will depend on the hardware that was used to attach it.

In most cases, you’ll need a screwdriver and a wrench that fits over the bolt.

As an example, I’ll walk you through how I removed my toilet seat. This is what it looked like from the top.

On the underside of the mounting holes, there was a plastic nut that secured the seat to the bowl. The screw threaded into the hinges at the top so there was no need for a screwdriver when I removed my toilet seat.

The plastic nut was actually very simple to remove. I adjusted my wrench to fit the nut dimensions and was able to unscrew it from the bolt with ease. The plastic nuts are actually ideal because they wont corrode over time. Just be careful and use moderate pressure when removing a plastic nut because it can be deformed very easily. If you have a hard time removing them with a wrench you can always cut them off.

Most toilet seats nowadays have plastic caps at the mounting holes (see example below). If the toilet seat that you need to remove has these, lightly lift the mounting cap to view the connection hardware. Once it is open you can assess the tools that will be needed to remove the toilet seat. In the example below, a phillips (crosshead) screwdriver would be needed to hold the plastic bolt in place while the nut on the underside of the toilet is loosened.

What if there are no visible screws?

Some of the newer toilet seats have a quick release design. There is a button on the underside of the toilet seat that when pressed releases the seat from the tank.

Replacing a toilet seat

Now that the old toilet seat is removed, let’s talk about how to install a new one.

First, remove the new toilet seat and hardware from the package. Be sure to read the manufacturers installation instructions to determine the exact tools and process required to install your new toilet seat.

I’ll walk you through how I installed my new toilet seat but keep in mind that the design of your toilet seat and the hardware may differ.

Align the hinges with the mounting holes on the toilet and align the length and width of the seat to match the toilet bowl. Then use the hardware that came with the new toilet seat to attach it to the bowl.

Here is an example of the underside of my toilet seat attachment. The new seat came with two plastic bolts and two plastic nuts that had a flange to hold on to while tightening the bolts from above.

I held on to the flange of the nut below and tightened the plastic nut from above using a wrench.

The newer toilet seat hardware design is pretty cool. You just continue tightening the nut on the top until it snaps off. Below the nut is a plastic head on the bolt that you can finish tightening with a screwdriver. If the hardware for your new seat is metal and not plastic, be very careful not to tighten the hardware too much. You could risk cracking the porcelain if it is too tight.