How to Replace a Toilet Step-by-Step

Whether you're giving your bathroom a fresh look, switching to a water-saving model, or dealing with a cracked bowl that's seen better days, replacing a toilet is a weekend project any handy homeowner can accomplish. We'll walk you through how to install a toilet from start to finish. 

If this is your first time tackling toilet repair or replacement, we recommend checking out our beginner's guide to fixing toilets to get familiar with the main parts. But here's a quick recap:

A standard two-piece toilet (the kind most folks have) is made up of:

• Bowl: The base unit that connects to the floor.
• Tank: Holds water and sits on top of the bowl. This is where the flush mechanism is.

Other key parts include:

• Closet bolts: Hold the toilet securely to the floor.
• Fill valve: Refills the tank after a flush.
• Flapper: Releases water into the bowl when you flush.
• Flush valve: The opening water flows through from the tank to bowl.
• Supply line: Connects to your home's water shutoff and feeds the toilet.
• Wax ring: Creates a watertight seal between the bowl and drainpipe.

This guide is focused on replacing a two-piece toilet, but other types exist, such as one-piece, wall-mounted, and dual flush. These follow similar principles but have their own instructions. 

Before we dive in, here are a few safety reminders:

• Turn off the water supply before starting. Trust us, it gets messy fast if you don't.
• Lift with your legs, not your back. Toilets are heavier than they look—don't hesitate to get a buddy to help.
• Use proper ventilation when you're using caulk or any strong adhesives. 

Here's your shopping list before you get started:

• New toilet (bowl + tank)
• New wax ring
• Putty knife
• Level
• Bucket
• Old towels or rags
• Adjustable wrench
• Rubber gloves (optional but recommended)
• Caulk (and a caulk gun)
• Caulk removal tool
• Screwdriver (depending on your toilet's hardware)
• Toilet seat (some new toilets come with one, but not always)

A good sense of humor will also go a long way.

Remove the Old Toilet

Start by turning off the water shutoff valve located behind the toilet. Flush the toilet to drain most of the water. Then, use a sponge or towel to soak up any leftover water in the tank and bowl.

Then, unscrew the closet bolts at the base of the bowl. Wiggle the bowl gently to break the wax seal and lift it straight up. It may take a little time, but slow and steady wins the race. You may also need to remove the caulk around the base. Stuff a rag in the floor drain to block sewer gas while you work.

Clean and Inspect the Flange

The closet flange is the round pipe fitting on the floor that connects the toilet to your plumbing. Scrape off the old wax ring using a putty knife and clean the area well.

Check the flange:

• Are the bolt slots damaged?
• Is it rusted through?
• Is it level?

This is a good time to replace it if it's in bad shape.

Install New Closet Bolts

Slide new closet bolts into the flange slots. These will hold the new toilet in place. Make sure they're aligned parallel to the wall behind the toilet.

Install the Wax Ring

Place the new wax ring on the flange or the bottom of the new toilet bowl (check your toilet manufacturer's recommendation). This sticky ring seals the connection between your toilet and the drainpipe.

Set the Bowl in Place

Carefully lift the new toilet bowl and lower it directly over the bolts and wax ring. Do not shift it once it touches down—you want a secure, straight seal.

Press down with your body weight to help the wax compress. Then, add the washers and wing nuts to the bolts and tighten them by hand. Don't overtighten—you could crack the porcelain. Once snug, snap on the decorative bolt caps.

Use a level side-to-side and front-to-back. If needed, use plastic shims to even things out.

Attach the Tank

Place the tank on the back of the bowl, lining up the bolt holes. Insert the tank bolts through the tank and tighten from underneath. Tighten until snug and level, but again—don't overdo it. You don't want to risk cracking the tank.

Install Flush Mechanism (if not pre-assembled)

Many new toilets come with fill valves, flappers, and flush valves that have already been installed. If not, follow the included instructions to assemble them inside the tank.

Connect the Water Supply

Reconnect the supply line to the bottom of the tank and slowly turn the water back on. Let the tank fill, then give it a test flush. Check for leaks around the base, supply line, or tank bolts. If you see drips, tighten connections slightly.

Add the Toilet Seat

Most modern toilet seats are installed with a simple screwdriver or quick-release mechanism. Line up the holes and secure them in place. 

Caulk the Base

Finally, run a bead of caulk around the base of the toilet. This helps keep out water, dirt, and mystery grime (you know the kind). Leave a small gap at the back so water can escape if a leak develops underneath.

All Done! Take a Victory Flush

That's it—you've just installed a toilet! Step back and admire your work. Go ahead, give it a celebratory flush. You've earned it.

Whether this is your first plumbing project or you've done a few before, installing a toilet is a great way to gain confidence and upgrade your home.

Need tools, materials, or a little extra advice? McCoy's Building Supply has everything you need—from wax rings to new toilets—and our team is always happy to help with your next DIY project. Stop by your local store or check out our selection online.