How to Replace a Bathroom Sink Faucet

Faucets are the hardest-working fixtures in your home, and over time, mineral buildup and failing seals make them more of a liability than a convenience. Replacing one isn't just about stopping a persistent drip; it is a straightforward upgrade that refreshes the entire look of your vanity without the need for a full renovation. Success in this project hinges on what happens beneath the basin. Since you will be working in a cramped, dark space, lighting and patience are your best tools. When done correctly, the new faucet will be rock-solid, leak-free, and perfectly aligned, turning a daily necessity into a smooth, reliable experience.

  1. Stop the water first. Locate the shut-off valves under the sink and turn them clockwise until they stop. Open the faucet handles to relieve remaining water pressure and ensure the flow has ceased.
  2. Free the supply lines. Place a bucket beneath the P-trap to catch residual water. Use an adjustable wrench to loosen the nuts connecting the water supply lines to the faucet shanks.
  3. Unbolt the old faucet. Use a basin wrench to reach the nuts securing the faucet to the underside of the countertop. Turn counter-clockwise to remove the nuts and washers from the mounting shanks.
  4. Scrub the deck clean. Lift the old faucet out from the top. Use a putty knife or non-scratch scouring pad to scrape away old plumber's putty or mineral deposits from the sink deck.
  5. Seat the new fixture. Place the new faucet's gasket or base plate over the sink holes, then feed the supply lines and shanks through. From underneath, tighten the mounting nuts until the faucet is firmly seated.
  6. Reconnect the water supply. Thread the supply lines onto the corresponding shut-off valves by hand, then tighten them an additional quarter-turn with a wrench. Do not overtighten, as this can crack the plastic or rubber seals.
  7. Verify it holds water. Slowly turn the water valves back on and check every connection for moisture using a dry paper towel. Run the faucet for a full minute to ensure the aerator is clear and the drain operates correctly.