Leaky faucet: how to fix the drip

Take the old part to the store: that's the whole secret.

The answer in 2 lines. A drip from the spout almost always comes from a worn washer or seat (older two-handle faucets) or a worn cartridge or ceramic disc (most faucets sold today). Shut off the water under the sink, take the handle off, pull the part and take it to the store to match it. Before you buy anything, check the brand: many big faucet makers offer a lifetime warranty and send replacement cartridges free.

The first 3 steps

Shut off the water: the small valves under the sink, or the main valve if there aren't any.
Open the faucet to drain what's left, and put the stopper in the drain so no small part disappears.
See where the water comes from: from the spout with the faucet closed, around the handle, or at the base of the spout.

Where it drips, and which part to change

A drip from the spout, faucet fully closed: worn washer or seat (compression faucet, the kind you turn several times to close), or worn cartridge or ceramic disc (single-handle and quarter-turn faucets). Usually DIY.
Water around the handle when it's on: worn O-ring or packing on the stem or cartridge. DIY.
Water at the base of a swivel spout: worn spout O-rings. DIY.
Water under the sink at a connection: the supply line or its fitting. DIY; tighten gently or replace the braided supply line.
A cracked faucet body, or one badly scaled: replace the faucet.

Not sure which type you have? Angi's guide shows the four common types (compression, cartridge, ball, ceramic disc) and how each comes apart.

Replacing the washer or cartridge, step by step

Water off, pry off the small cap on the handle, remove the screw, and pull the handle off.
Unscrew the stem or remove the cartridge's retaining nut or clip, protecting the chrome with a cloth. Hold the faucet body so it doesn't twist.
Compression faucet (several turns to close): replace the rubber washer held by a screw at the bottom of the stem, and the O-ring.
Cartridge or ceramic disc (quarter turn or single lever): usually you replace the whole cartridge. Note which way it faces before pulling it out.
Take the old part to a hardware store or home center: length, diameter and the number of splines on the stem must match. The brand name on the faucet and a photo help.
Reassemble without forcing, turn the water back on slowly and check that the drip has stopped.

Check the warranty first

Many major faucet brands offer a lifetime limited warranty for the original buyer, often covering leaks and drips, and send replacement parts free. Moen explains its warranty and how to identify your model online (Moen lifetime limited warranty; identify my Moen product).
How to choose: look for the brand name on the handle, the base or the escutcheon plate, then go to that brand's customer-support page and search "warranty" or "replacement parts". Have a photo and, if you have it, the model number from the box or the receipt.
Warranties usually cover parts, not a plumber's labor, and may be limited for rentals or commercial use. Read the terms.

What not to do

Cranking the handle tighter and tighter to stop the drip: you crush the washer and damage the seat.
Taking the stem or cartridge out without shutting off the water.
Using bare pliers on chrome: it scratches, and the nut gets rounded.

If the drip comes back quickly

On a compression faucet, the seat (the surface the washer presses against) may be pitted or scaled. It can be replaced with a seat wrench, or resurfaced with a seat dressing tool; otherwise, replace the faucet.
In hard water, washers and O-rings stiffen faster: soaking the removed parts in white vinegar helps clean them.
An old faucet whose parts can't be found is best replaced: new faucets come with instructions and seals. When you choose one, match the number of holes in your sink or countertop (one, three or a wide spread) and look for the WaterSense label on bathroom faucets.

Good to know

A dripping faucet wastes water day and night, and if it's the hot side, you're paying to heat it too. It's often the easiest and cheapest leak to fix.

Who pays?

Renters: in most states, landlords must keep plumbing in good working order under the implied warranty of habitability (FindLaw: the implied warranty of habitability). A small drip may not make a home unlivable, so check your lease: report it in writing and ask before fixing it yourself. See our guide on repairs between tenant and landlord.
Homeowners: the repair is yours. Some water utilities offer a leak adjustment on the bill once a leak is fixed; ask yours, it's not automatic.

In Raleigh, Priya hears a drip in the bathroom sink all night. She shuts off the valve under the sink, pulls the handle and finds a Moen cartridge. She orders a free replacement through Moen's warranty page, installs it a few days later in ten minutes, and the sink is quiet.

A made-up story, for illustration.

The numbers (latest published)

More than 3,000 gallons a year: what a faucet dripping once a second can waste, according to EPA WaterSense (EPA Fix a Leak Week fact sheet). It's EPA's standing estimate, not a new 2026 measurement.
Nearly 10,000 gallons a year: average household water lost to leaks of all kinds, per EPA figures repeated for Fix a Leak Week in March 2026 (Michigan EGLE).

Bobby

Sources, verification, confidence

Verified on November 1, 2026, for the United States. Confidence: high for the repair steps and safety; medium for the water-loss figures (EPA estimates, not new measurements), for warranty terms, which vary by brand and model (read yours), and for who pays in a rental, which depends on your state and lease.