How to Replace a Bathroom Sink Faucet

Faucets are the workhorses of the bathroom, but over time, mineral deposits and worn internal washers turn a simple handle turn into a drip or a leak. Replacing a bathroom faucet is a high-impact project that refreshes the entire vanity while eliminating those annoying plumbing failures. It is a straightforward task that requires little more than patience and access to the cramped space under your sink. Success here is measured by a dry connection and a smooth flow. The secret to a leak-free install isn't brute force; it is ensuring that your rubber gaskets are seated perfectly and that your supply lines are tightened just enough to stop water, but not enough to crush the plastic fittings. Take your time clearing out the cabinet, and you will have this done before lunch.

  1. Shut Off Water First. Empty your under-sink vanity completely to give yourself room to maneuver. Locate the shut-off valves under the sink and turn them clockwise until they stop; open the faucet handles to bleed out any remaining pressure.
  2. Disconnect Old Supply Lines. Use an adjustable wrench to loosen the nuts connecting the supply lines to the shut-off valves. Once those are loose, unscrew the supply lines from the base of the old faucet.
  3. Loosen Mounting Nuts. Reach behind the sink basin and unscrew the mounting nuts securing the faucet to the countertop. You may need a basin wrench if the space between the sink and the wall is too tight for a standard wrench.
  4. Clean Mounting Surface. Remove the old faucet from the top of the vanity and scrape away any leftover putty or gunk using a plastic putty knife. Wipe the surface clean with a damp cloth and ensure it is completely dry before proceeding.
  5. Secure New Faucet. Place the new faucet gasket on the base, feed the lines through the mounting holes, and secure the faucet from underneath using the provided washers and nuts. Ensure the faucet is perfectly aligned with the sink before tightening the nuts firmly.
  6. Connect Supply Lines. Thread the supply lines onto the new faucet shanks and the shut-off valves, tightening them with your wrench until snug. Turn on the shut-off valves slowly and check for any immediate moisture at the connections.