How to Replace a Bathroom Faucet

Replacing a bathroom faucet is one of the most satisfying plumbing jobs you can do yourself, and it doesn't require special skills or expensive tools. A leaky faucet, mineral buildup, or simply wanting a new look are all valid reasons to swap it out. The job is straightforward: you're essentially undoing old connections, removing the old faucet, and fastening a new one in its place. What matters most is working methodically, having the right supplies on hand, and understanding your water shutoff before you start. A successful replacement means no leaks, proper water pressure, and a bathroom that works and looks the way you want it.

1. Kill the Flow First. Locate the shutoff valves under the sink—there's usually one for hot and one for cold water. Turn both clockwise until they stop. If you can't find them or they don't work, shut off the main water supply to the house. Turn on the faucet to release any remaining pressure in the lines.
2. Unthread the Old Lines. Place a small bucket or towels under the shutoff valves. Use an adjustable wrench to unscrew the compression nuts connecting the supply lines to the valve stems. Keep the nuts and washers—you may reuse them. Set the lines aside.
3. Yank Out the Old Unit. Look under the sink for the mounting nuts holding the faucet to the counter. Use a basin wrench (a specialized tool that grips nuts in tight spaces) or an adjustable wrench to loosen and remove these nuts. Once loose, pull the old faucet up and out of the counter hole. Clean any mineral deposits or old caulk from the counter surface with a rag.
4. Seat the New Faucet. Insert the new faucet into the counter holes (most modern faucets use a single hole or three-hole setup—verify yours matches your counter). From underneath, install the mounting hardware according to the manufacturer's instructions. Hand-tighten the mounting nuts first, then use your wrench to snug them firmly but without excessive force. The faucet should sit flush and stable on the counter.
5. Hook Up the Lines. If your new faucet comes with new supply lines, attach them to the faucet inlet ports (usually two on the base). Then connect the other ends to your shutoff valves, hand-tightening first and then using your wrench to seat the compression nuts. Connect hot water to the hot valve and cold to cold. Turn the shutoff valves counterclockwise to restore water pressure.
6. Verify No Leaks Exist. Turn on the faucet and let hot and cold water run for 30 seconds. Check under the sink for any drips around the supply connections and the mounting area. If you see leaks at the compression nuts, turn off water and tighten a quarter-turn more, then test again. Let the faucet run and feel both temperatures to confirm everything works.
7. Seal and Cleanup. If there are gaps between the faucet base and counter, apply a thin bead of silicone caulk (clear or white) and smooth it with a wet finger. Let it cure per the manufacturer's time (usually 24 hours). Wipe down the counter and faucet, and dispose of the old faucet and any packaging.