To fix a dripping faucet, first close both supply stops under the sink and open the faucet to release the pressure, then plug the drain so nothing small disappears. Next, identify what is inside it. A two-handle compression faucet has a rubber washer and a valve seat. A single-handle faucet almost certainly has a cartridge, a ceramic disc or a ball assembly, and none of those contain a washer at all. The part you replace depends entirely on which one you own.
That last sentence is why so much faucet advice fails. "Replace the washer" is the answer to a faucet design that has been out of the mainstream for decades, and if you own a modern single-handle mixer, there is no washer in it to replace.
Before you touch anything: three steps that prevent the expensive version
Close the stops, both of them. Two small valves under the sink, hot and cold. Close both, even if only one side drips, then open the faucet to let the pressure out and to confirm the water has actually stopped. If a stop will not close fully, or will not turn at all, stop here. That is a licensed plumber's small job, and taking a faucet apart above a supply you cannot shut off is how a drip becomes a flood.
Plug the drain. Screws, clips, retaining nuts and springs are all small and the drain is right there. A rag in the opening does the job.
Find out what you own. Look for a brand on the spout or handle, then find the model. Manufacturers publish parts diagrams by model and most repairs are simply a matter of ordering the right one. Moen's own troubleshooting guidance for a bathroom faucet dripping from the spout, read on 2026-09-08, says that if a faucet is leaking water from the spout the reason is usually the cartridge, that single-handle faucets contain one cartridge and dual-handle faucets have two, and that the model number is what gets you the right parts sheet. That is the manufacturer describing its own product, which beats any generic instruction.
Take photographs as you disassemble. Not for the internet. For you, in forty minutes, when the order of two parts is no longer obvious.
How to fix a dripping faucet: four designs, four different failures
| Faucet type | How to recognize it | What actually fails | What you replace |
|---|---|---|---|
| Compression | Two handles that keep turning tighter, older installation | Rubber washer flattens, and the brass valve seat pits | Washer and seat, and the seat may need a seat wrench or dressing tool |
| Cartridge | One handle that moves up and down and side to side, or two handles that stop at a quarter turn | The cartridge itself wears, or its O-rings tear | The whole cartridge, matched to the model |
| Ceramic disc | Single lever, wide cylindrical body, smooth short travel | Neoprene seals scale up, or the disc surface is scored | Seals cleaned or replaced, or the whole disc cartridge |
| Ball | Single lever with a rounded cap, common on older kitchen faucets | Springs and rubber seats under the ball wear | The kit: springs, seats, ball, cam |
Compression. The only one where "it is the washer" is true, and even then it is often only half true. A washer that has been pressed against a pitted seat wears out again quickly, so if a new washer drips within weeks, the seat is the reason.
Cartridge. The most common design in homes today. The cartridge lifts out as a unit once the handle and the retaining clip or nut are off. The one thing to know before you start is that a cartridge that has been in place for years can be stubborn to withdraw, and forcing it can damage the faucet body. Manufacturers sell a puller for exactly this, and if the faucet body is what breaks, you are now replacing the entire faucet.
Ceramic disc. Long-lived, and when it does drip, mineral scale on the seals is a frequent culprit. If the ceramic surface itself is scored, the cartridge is replaced rather than serviced.
Ball. Repaired from a kit rather than a single part, because the springs, seats, ball and cam wear as a set.
Where the drip is coming from changes the diagnosis
This is the step most guides skip, and it saves people from opening the wrong thing.
Dripping from the spout when the faucet is off. The valve is not sealing. This is the cartridge, disc, ball or washer, as above.
Water seeping around the base of the spout when the water runs. Usually the O-rings on the spout body rather than the valve. A different part, a different job.
Leaking from under the handle. Often the packing nut, the bonnet or an O-ring at the stem.
A puddle in the cabinet with a dry faucet. The leak is at a supply line, a stop, or the drain. Check whether the water appears only when the faucet runs, which points at supply or drain, or continuously, which points at supply.
Water at the wall or the ceiling below. Not a faucet job. Stop and call a licensed plumber. Anything behind a wall, including a tub or shower valve body, is not a fixture repair.
Why it is so often not the washer, and what actually kills the part
If you have a cartridge, a disc or a ball faucet, there is no washer in the assembly. The failing components are rubber seals and precision surfaces, and the thing that wears them out fastest is what is in your water.
Mineral scale builds on seals and seating surfaces, holds them a fraction of a millimeter off true, and the faucet drips. It is the same process that leaves crust on an aerator and film on glassware. If you already recognize that pattern in your house, expect faucet cartridges to be a recurring rather than a once-a-decade job. Getting a real answer about your supply, rather than guessing from a national hardness map, is covered in the signs of hard water in the house.
There is a cheap household test for the same question. If your kettle furs up within weeks of descaling, the water going through your faucet cartridge is doing the same thing to it, and how often to descale a kettle explains why no authority publishes a universal interval for it either.
An aerator worth checking while you are there: unscrew it, look for grit and scale, soak it and refit it. It will not stop a drip, but it fixes the weak, spitting flow that people often assume is a failing faucet.
What the drip is costing while you decide
The EPA's Fix a Leak Week page, updated March 2026 and read on 2026-09-08, states that a leaky faucet dripping at the rate of one drip per second can waste more than 3,000 gallons per year, that a showerhead leaking at 10 drips per minute wastes more than 500 gallons per year, and that the average household's leaks can account for more than 9,300 gallons of water wasted every year.
That is the honest argument for fixing it: not a dramatic bill, but a steady one, and the drip is also telling you a part has failed rather than that a faucet is being temperamental.
Before you crawl under the sink, know what else lives there
The cabinet under a kitchen sink is crowded, and two of the things in it are frequently blamed on the faucet.
A dishwasher's supply line and drain hose usually run through that cabinet, and standing water inside the machine is a drain problem rather than a supply one. A dishwasher that will not drain has its own sequence and closing the faucet stops will not affect it.
A smell rather than a puddle is also a different problem, and it usually comes from the trap, the disposal or the vent rather than from anything you are about to unscrew. A kitchen sink that smells like sewage covers where it actually comes from.
Where this stops being yours
Every one of these is a licensed plumber, and none of them is a confidence question.
- A supply stop that will not close, or that will not turn. Do not proceed with the repair. Replacing a stop is plumbing work under pressure.
- A stop that closes but still passes water. Same answer. You have no reliable isolation.
- Corroded, seized or rounded nuts on supply lines or the faucet body. Force here breaks a fitting you cannot shut off.
- Galvanized or otherwise brittle old pipework. Turning a connection can crack the pipe further back, inside a wall.
- Any leak behind a wall, inside a floor, or appearing at a ceiling below. Immediate call, and shut off the main first.
- A tub or shower valve body. In the wall, and its own job.
- No shutoff for the fixture and no accessible main. Get the shutoff installed first, as a planned job, before any repair is attempted.
- A faucet that still drips after the correct part has been replaced properly. Often a pitted seat or a damaged faucet body, and at that point replacement of the faucet is usually the cheaper answer.
One last honest note. On an inexpensive faucet, the parts plus a special tool can approach the cost of a new faucet, and installing a new one is a bigger job than replacing a cartridge because it involves the supply connections underneath. Neither choice is wrong. It is worth pricing both before you start rather than halfway through.
FAQ
Why is my faucet still dripping after I replaced the washer? Most likely because the faucet does not use a washer, or because the valve seat behind the washer is pitted. Single-handle faucets almost always use a cartridge, ceramic disc or ball assembly, and Moen's own guidance is that a spout drip is usually the cartridge.
How do I know which type of faucet I have? Two handles that keep tightening as you turn them is compression. A single lever, or handles that stop after about a quarter turn, means a cartridge, ceramic disc or ball. The brand and model number on the faucet gets you the manufacturer's own parts diagram, which settles it.
Do I have to turn off the water at the main to fix a faucet? Usually not. Close both supply stops under the sink and open the faucet to release pressure. If either stop will not close, do not continue, and call a licensed plumber to replace the stop.
How much water does a dripping faucet waste? The EPA states that a faucet dripping at one drip per second can waste more than 3,000 gallons a year, and that household leaks overall average more than 9,300 gallons a year.
Why do my faucet cartridges keep failing? Hard water is the usual reason. Mineral scale builds on the seals and seating surfaces so they no longer close cleanly. Confirming your water hardness with your utility tells you whether to expect this as a recurring job.
Is it worth repairing a faucet or replacing it? Repair is usually cheaper and quicker when the part is available and the stops work. Replacement makes more sense when the faucet body is damaged, when the finish is failing anyway, or when the parts and tools approach the price of a new fixture.
