How to Replace a Bathtub Drain Flange

Step 1: Make sure the flange is really the problem

1. Look at the drain opening and the visible flange from inside the tub.
2. Replace the flange if it is heavily rusted, cracked, pitted, loose, or if the crossbars are broken and the part will not hold or seal properly.
3. Wipe the area dry, then run a small amount of water around the drain and watch for seepage at the tub surface or signs that the flange no longer sits flat.
4. If you have access behind or below the tub, use a flashlight to look for obvious damage to the drain shoe or surrounding piping before you start.

If it works: You have a clear reason to replace the bathtub drain flange and the visible drain body appears intact enough for a flange swap.

If it doesn’t: If the flange looks fine and the problem is a slow drain, try cleaning hair and debris from the drain first instead of replacing the flange.

Step 2: Prep the tub and remove the old flange

1. Lay a rag in the tub to protect the finish and catch debris.
2. Remove any stopper parts that block access to the flange opening.
3. Insert the tub drain wrench into the flange and turn counterclockwise using pliers if needed for leverage.
4. Work slowly if the flange is stuck. Short, controlled turns are better than forcing it hard enough to damage the drain shoe below.
5. Lift the old flange out once the threads release.

Step 3: Clean the drain opening and inspect the threads

1. Scrape away all old plumber's putty, sealant, soap scum, and rust from the tub surface around the drain with a plastic putty knife.
2. Wipe the area clean and dry so the new flange can seat flat.
3. Inspect the female threads in the drain shoe for damage, heavy corrosion, or leftover debris.
4. Test-fit the new flange by hand for a turn or two without sealant, then back it out.

Step 4: Seal and install the new flange

1. Roll a small rope of plumber's putty and press it under the lip of the new flange, unless the replacement specifically uses a different seal method.
2. Set the flange into the drain opening and thread it in by hand first to avoid cross-threading.
3. Tighten it with the drain wrench until the flange is snug and seated evenly against the tub surface.
4. Do not overtighten. The goal is a firm seal, not maximum force.
5. Wipe away the excess putty that squeezes out around the flange.

Step 5: Reassemble the drain and clean up

1. Reinstall any stopper parts you removed earlier.
2. Wipe the tub surface clean so you can spot fresh moisture during testing.
3. If you have access below the tub, place a dry paper towel under the drain area to make leak checks easier.

If it doesn’t: If the stopper no longer fits or moves correctly, check that the replacement flange is the right style for your drain setup.

Step 6: Test the repair in real use

1. Run a small amount of water first and watch around the flange for seepage.
2. Then fill the tub with a few inches of water and let it sit briefly so the flange seal is under normal use conditions.
3. Drain the tub while watching the flange area and, if accessible, the drain shoe below for drips.
4. Check again after the tub has fully drained and the piping has stopped moving.

If it works: The flange stays dry at the tub surface, no water appears below the tub, and the drain works normally.

If it doesn’t: If you see seepage at the tub surface, remove the flange, clean everything again, and reseal it with fresh putty before retesting.