What you need to know before you start

Removing and replacing a toilet is a project most homeowners can do in two to four hours with basic tools and no plumbing experience. The work is straightforward: shut off the water, drain the tank and bowl, unbolt the toilet from the floor, remove the old wax ring, install a new one, and bolt down the new toilet. The hardest part is usually breaking the seal on an old toilet or lifting a heavy porcelain bowl—not the mechanics of the job itself.

You will need a wrench, a screwdriver, a putty knife, a bucket, towels, and a new wax ring (the rubber seal between the toilet and the drain pipe). If you are replacing the toilet, buy the new one before you start so you know it will fit your space and rough-in distance—the distance from the wall to the center of the drain hole, usually 12 inches in most homes. If the new toilet has a different rough-in, you may need a plumber to move the drain pipe, which is beyond this project.

Key Takeaways

  • Turn off the water at the shutoff valve under the tank, flush to empty the bowl, and sponge out any remaining water before you unbolt anything.
  • The toilet is held down by two bolts on either side of the base; remove the caps, unscrew the bolts, and rock the toilet gently to break the wax seal.
  • Scrape off all old wax and debris from the flange (the ring on the floor), then press a new wax ring firmly onto the flange before setting the new toilet.
  • Set the new toilet straight, press down evenly, hand-tighten the bolts, then use a wrench to snug them—do not over-tighten, which can crack the porcelain.
  • Reconnect the water supply line, turn the water back on, and let the tank fill and refill once to check for leaks before you use the toilet.

Turn off the water and drain the toilet

Locate the shutoff valve on the water supply line under the tank, on the left side. Turn the handle clockwise until it stops. If the valve is stuck or leaking, you may need to shut off the main water supply to the house instead—usually a valve near the water meter or where the line enters the house.

Flush the toilet to empty the tank. Use a sponge or towel to soak up any water remaining in the bowl and tank. Wring the water into a bucket. This step prevents spills when you disconnect the supply line and remove the toilet. If water drips from the tank bolts or supply line, place a towel underneath.

Disconnect the water supply line

The supply line is a flexible hose or rigid tube connecting the shutoff valve to the bottom of the tank. Use an adjustable wrench to hold the fitting at the shutoff valve with one hand while you turn the nut on the supply line counterclockwise with the other. Once the nut is loose, unscrew it by hand and pull the line away.

If the line is rigid copper or steel, you may need two wrenches—one to hold the fitting at the tank and one to turn the nut at the valve. Work slowly to avoid stripping the nut. If the line is old and brittle, it may crack; if that happens, you will need to replace it with a new flexible supply line before you install the new toilet.

Remove the bolts and lift out the old toilet

Look at the base of the toilet on both sides. You will see a plastic cap or bolt cover on each side. Pry off the caps with a screwdriver or your fingernail. Underneath are the bolts that hold the toilet to the floor flange.

Use an adjustable wrench to turn each bolt counterclockwise. If a bolt spins without loosening, the nut underneath the flange is turning too. Slide under the toilet with a wrench or socket to hold the nut still while you unscrew the bolt from above. Once both bolts are loose, remove them completely.

Rock the toilet gently side to side and front to back. This breaks the seal created by the old wax ring. Once the seal breaks, you should be able to lift the toilet straight up. It is heavy—usually 80 to 100 pounds—so ask someone to help or use your legs, not your back. Set the toilet on its side on a towel or cardboard to protect the floor.

Clean the flange and install the new wax ring

The flange is the ring bolted to the floor where the drain pipe comes up. It is usually made of plastic, metal, or cast iron. Scrape off all old wax, putty, and debris using a putty knife. Work carefully so you do not damage the flange itself. Once it is clean and dry, inspect it for cracks or breaks. If the flange is cracked or broken, you will need a plumber to repair or replace it before you install the new toilet.

Press a new wax ring firmly onto the flange, centered over the drain hole. The ring should stick to the flange on its own. Do not remove the backing yet—most wax rings come with a paper or plastic backing that you peel off just before you set the toilet. If your ring does not have backing, install it now and be careful not to disturb it when you lower the toilet.

Set the new toilet and bolt it down

Position the new toilet over the flange so the bolts on either side line up with the bolt holes in the base. Lower the toilet straight down onto the wax ring. Do not twist or rock it side to side, as that can break the seal. Press down firmly and evenly with your weight to compress the wax ring.

Insert the bolts through the holes in the base and thread them into the flange. Hand-tighten them first, then use a wrench to snug them. Tighten each bolt a little at a time, alternating sides, so the toilet sits level. Do not over-tighten—porcelain cracks easily. The bolts should be snug enough that the toilet does not rock, but you should still be able to turn them with moderate pressure from a wrench.

Once the bolts are tight, snap the plastic caps back on or install new ones if they came with the new toilet. Check that the toilet sits level by placing a level on the rim. If it rocks, loosen the bolts slightly and shim under the base with plastic shims until it is level, then re-tighten.

Reconnect the water supply and test for leaks

Connect the supply line to the shutoff valve and hand-tighten the nut. Use a wrench to snug it—again, snug but not over-tight. Turn the shutoff valve counterclockwise to turn the water back on. Water should flow into the tank.

Let the tank fill completely, then flush. Watch for leaks around the base of the toilet, at the supply line connection, and at the tank bolts. If you see water pooling under the toilet, the wax ring may not have sealed properly. Turn off the water, drain the toilet, and remove it again to check the flange and wax ring. If the leak is at the supply line or tank bolts, tighten those connections slightly.

Flush a second time and let the tank refill to make sure everything is working. The toilet is ready to use once the tank fills without leaking and the bowl drains normally.

When to call a plumber

Call a plumber if the flange is cracked, broken, or sits below the floor level—these problems prevent a good seal and require professional repair. Also call if the shutoff valve will not turn off or leaks, if the supply line is rigid and you cannot disconnect it, or if the new toilet does not fit the rough-in distance of your drain pipe.

If you remove the old toilet and water backs up into the bowl or overflows, the drain line may be blocked. A plumber can clear it with a snake or auger. Do not attempt this yourself unless you have experience, as you can damage the line.

Frequently Asked Questions

Can I reuse the old wax ring?

No. Wax rings are single-use and lose their seal once they are compressed. A used ring will not seal properly on a new toilet and will leak. Always buy a new wax ring for each installation. They cost a few dollars and are available at any hardware store.

What if the old bolts are rusted and will not turn?

Spray the bolts with penetrating oil (like WD-40) and wait 15 to 30 minutes. Try again with a wrench. If they still will not budge, you may need to cut them with a hacksaw or rotary tool. Work carefully to avoid damaging the flange or porcelain. Once the bolts are out, replace them with new stainless steel bolts when you install the new toilet.

How do I know if my new toilet will fit?

Measure the rough-in distance—from the wall behind the toilet to the center of the drain hole. Most homes have a 12-inch rough-in, but some have 10 or 14 inches. Measure before you buy. Also check the width of your bathroom and the height of the ceiling to make sure the new toilet fits the space. Bring these measurements to the store when you shop.

What if water leaks from under the toilet after I install it?

Turn off the water, drain the toilet, and remove it again. The wax ring may not have seated properly, or the flange may be damaged or uneven. Clean the flange, install a new wax ring, and reinstall the toilet, pressing down firmly. If the leak continues, the flange may need repair by a plumber.

Do I need to caulk around the base of the toilet?

Caulking is optional and does not affect the seal. Some people caulk for appearance or to prevent water from running under the toilet if it overflows. If you caulk, use silicone caulk and leave a small gap at the back so water can escape if there is a leak—this helps you spot problems early.