Fix a Leaking Bathroom Faucet

A dripping faucet is one of those small annoyances that compounds. One drop per second adds up to hundreds of gallons a year wasted, plus the sound of it will drive you to fix it eventually anyway. The good news: bathroom faucet leaks are almost always fixable without replacing the whole fixture, and you don't need a plumber. The leak happens because washers, O-rings, or valve seats inside the faucet wear out over time. Water finds its way past these seals and drips. The fix is straightforward—turn off the water, take the faucet apart, swap out the worn pieces, and reassemble. Once you've done it once, you'll recognize the problem immediately if it happens again. The trickiest part isn't the repair itself; it's knowing which type of faucet you have. Single-handle, double-handle, cartridge, ceramic disc—each design comes apart differently. But the principle is the same: isolate the water, access the internal parts, identify what's worn, and replace it. This guide covers the two most common bathroom faucet types. If your faucet is unusual or cartridge-based, the concepts transfer, but you may need to consult the manufacturer's diagram.

1. Shut Off the Water First. Locate the shut-off valves under the sink. There should be two small knobs or levers—one for hot water, one for cold. Turn them both clockwise until they stop. Don't force them; they only need firm pressure. If there are no shut-off valves under the sink, turn off the main water supply to the house, which is usually in the basement, garage, or near the water meter.
2. Block the Drain Now. Use a wet cloth, plastic bag, or drain stopper to block the sink drain completely. When you disassemble the faucet, small parts will fall, and the drain is a one-way trip to behind the wall or into the p-trap.
3. Pop Off the Cap. Look for a small decorative cap, button, or trim ring on top of or behind the faucet handle. It's usually plastic, chrome, or painted to match the finish. Use a flathead screwdriver or your fingernail to pry it off gently. Don't stab the faucet itself; work at the seam. The cap will pop off, revealing the handle screw beneath.
4. Free the Handle. Unscrew the screw holding the handle in place using a Phillips or flathead screwdriver, depending on your faucet. This screw is usually small and doesn't need much force—hand-tight is enough. Once it's out, pull the handle straight up and off. If it's stuck, wiggle it gently side to side rather than yanking.
5. Loosen the Packing Nut. Below where the handle was, you'll see a hexagonal nut (the packing nut) screwed onto the faucet body. Use an adjustable wrench or a wrench that fits snugly. Turn it counterclockwise to loosen and unscrew it by hand. This nut holds the valve stem in place. Set it aside.
6. Extract the Valve Stem. Once the packing nut is off, you can pull the valve stem straight up and out. It will come free with a gentle tug. Inside the stem or directly below it, you'll see a rubber washer on the bottom and possibly O-rings around the stem itself. This is where the leak is coming from. Lay the stem on a clean surface so you can see all the parts.
7. Find the Worn Parts. At the bottom of the valve stem, you'll find a small rubber washer held in place by a brass screw. Remove the screw (it's tiny), take out the old washer, and set aside the screw. Then, slide the rubber O-rings off the stem body. The washers are usually deteriorated—cracked, flat, or missing entirely. The O-rings may be hardened or flattened. This is the root of your leak.
8. Clean Everything. While the stem is out, use a clean cloth and white vinegar to wipe away any mineral deposits, sediment, or corrosion from the stem itself and from inside the faucet body where the stem sits. A white, crusty buildup is mineral scale from hard water. Scrub it away gently—you don't need to strip the finish, just clean the surfaces where the new washer and O-rings will seal. This step makes a huge difference in how well the repair holds.
9. Install New Seals. Slide the new O-rings onto the valve stem first. They should fit snugly but not require force. Then, position the new washer at the bottom of the stem, holding it in place with the brass screw. The screw only needs to be finger-tight—over-tightening will compress the washer and cause it to fail faster. The washer should sit flat and centered on the stem end.
10. Seat the Stem. Slide the valve stem straight back down into the faucet body, aligning it the way it was when you removed it. It should slide in smoothly without resistance. If it's tight or won't seat, stop and check that the O-rings are properly positioned and the stem is straight. Once it's fully seated, screw the packing nut back on by hand first, then tighten it with a wrench until it's snug—not cranked hard, just firm.
11. Reattach the Handle. Slide the handle back onto the stem and insert the handle screw. Tighten the screw by hand, then give it a final quarter-turn with a screwdriver. Don't over-tighten—the handle should sit firmly and not wobble, but it shouldn't feel like you're crushing it. Once the screw is set, pop the decorative cap back on by pressing it into place until it clicks or snaps flush.
12. Restore Water Flow. Turn the shut-off valves back on—counterclockwise—slowly and steadily. Listen for the hiss of air leaving the lines. Once the hissing stops and water flows, turn the faucet handle on and off a few times to run water through and check for leaks. Inspect the base where the faucet meets the sink and underneath at the valve connections for any drips.
13. Verify No Leaks. Crawl under the sink with a flashlight and watch the shut-off valve connections and the base of the faucet where it passes through the sink. Let the faucet run for a minute. A properly sealed faucet should show no drips. If you see water dripping from the packing nut area, tighten it slightly more. If water drips from the sink base, the faucet body itself may be damaged, and you'll need to replace the whole faucet.