Why Is My Faucet Dripping?
A faucet that keeps dripping after you shut it off has a worn cartridge, washer, seat or set of seats and springs. Which one depends on the kind of faucet. How to tell in a few minutes, and what to check before you buy a part.
Updated
On this page
Short answer. A drip that keeps going with the handle off means the sealing part has worn. What that part is depends on the faucet: a cartridge in most single-handle faucets, a washer and seat in older two-handle faucets, a ceramic disc unit in newer two-handle faucets, and seats and springs in single-handle ball faucets. A drip that stops within a minute or two is usually just a dirty aerator draining.
First, the two-minute check
Turn the faucet fully off and watch the spout.
- It drips for a minute or two, then stops. Water is draining out of the aerator, the screen at the tip of the spout. Unscrew it and soak it in a 50/50 mix of warm water and white vinegar. Kohler gives the same fix for this exact pattern.
- It keeps dripping, steadily. Something inside the valve is no longer sealing. That is a part, not a cleaning job.
- The spout is dry, but water shows up around the handle or base. Different problem. See faucet leaking from the handle or base.
Know what kind of faucet it is
This decides which part you are looking for. On a single-handle faucet you only know for sure once the handle is off, because a ball valve and a cartridge can wear the same handle.
| What you see | What is inside | What usually causes the drip |
|---|---|---|
| One handle; under it, a cap and a ball with holes in it | Ball valve, no cartridge | Worn rubber seats and springs under the ball |
| One handle; under it, a cylinder held by a nut or clip | Single-lever cartridge | Worn or scored discs or seals in the cartridge |
| Two handles that turn several full turns and need force to stop | Compression stems with washers | Worn washer, or a pitted seat |
| Two handles that turn about a quarter turn and stop | Ceramic disc units | Scored disc faces or a hardened bottom seal |
| Drips a minute or two after shutoff, then stops | Any faucet | Water draining from a clogged aerator |
The fix for each kind
Ball faucets. There is no cartridge. The ball sits on two small rubber seats pushed up by springs, and those seats wear. A seats and springs kit fixes the drip. If someone tells you to buy a cartridge for this faucet, check what is under the cap first.
Single-lever cartridge faucets. The cartridge controls both volume and temperature, and when it drips with the handle off its discs or seals are worn. Replace the cartridge. Moen’s guidance for a leaking single-handle faucet is the same. Pull the whole cartridge to identify it, not just the stem, and measure its diameter: single-lever cartridges that look alike often differ by a few millimeters.
Compression faucets. The stem screws down and presses a rubber washer onto a brass seat. A worn washer drips. So does a pitted seat, which is why some faucets keep dripping after a new washer. Replace the washer, and the seat too if it unscrews. Stem units are often sold without the seat, so check before you order.
Ceramic disc two-handle faucets. Each handle has its own quarter-turn unit with two ceramic discs. Grit or scale scores the disc faces and the drip starts. Replace the unit on the leaking side. Hot and cold units on the same faucet are often mirror images that close in opposite directions, so they are not always interchangeable.
What the parts counter will ask you
Before ordering, have these answers. A good parts counter asks for them in roughly this order, and a part matched on only one of them is a guess.
- What kind of valve it is, from the table above.
- The top of the stem: how many splines (the teeth the handle grips), or its shape if it is not splined.
- The overall length, with the part out, against a tape.
- The diameter, for single-lever cartridges especially.
- Which way it turns off. Hold the old part by the stem and turn it to its closed stop. Many two-handle sets close in opposite directions on each side.
- Which side it came off, hot or cold.
- Anything between the handle and the part, like an extension or adapter, that you will need to reuse.
What to do next
- Shut off the supply valves under the sink and open the faucet to drain it.
- Take the handle off. The screw is usually under a decorative cap, or it is a small set screw on the side or back of the handle.
- Pull the part held by the nut, clip or bonnet, and note which way it faced.
- Answer the counter questions above and match the replacement exactly.
Brand guides walk through the removal: Moen, Delta, Kohler and Pfister.
No brand, no number, no luck with a chart
Charts and part finders work when the part has a readable number or the faucet has a known brand. The faucets that drip most often are the ones they fail on: older units, builder-grade and store-brand faucets, worn or painted trim, discontinued lines.
Photograph the part you pulled next to the handle, or the handle and trim if you have not pulled it yet, and a specialist identifies the replacement. If you can measure it, the CID Finder narrows it by length, spline count and stem shape. The method is laid out in how to identify a faucet cartridge.
When to call a plumber
Bring in a pro when the valve body is cracked or corroded, when a stem is seized and will not come out without force, when a seat is part of the body and needs dressing, when the supply valves will not close, or when the faucet is built into the wall.
Common questions
Why is my faucet dripping when it is turned off?
Water is getting past the part that is supposed to seal. Which part depends on the faucet: a cartridge in most single-handle faucets, a washer and seat in older two-handle compression faucets, a ceramic disc unit in newer two-handle faucets, and rubber seats and springs in single-handle ball faucets. A drip that stops after a minute or two is usually water draining from the aerator, not a failed part.
I replaced the washer and it still drips. Why?
On a compression faucet the washer seals against a brass seat in the faucet body. If the seat is pitted or worn, a new washer cannot seal against it. Replace the seat if it unscrews, or have it dressed if it is part of the body.
Can a dripping faucet fix itself?
No. Seals and ceramic discs wear or get scored by grit, and the drip gets worse over time. Cranking a compression handle harder can stop it for a while, but it crushes the washer faster.
Which side is dripping, hot or cold?
Shut off the hot supply valve under the sink and open the faucet briefly to drop the pressure: if the drip stops, it is the hot side. Feeling the drip only works right after hot water has run, because water sitting in the line cools. Two-handle faucets often have a different part for each side, so note which side the old one came from.
How much water does a dripping faucet waste?
The EPA estimates that a faucet dripping once per second wastes more than 3,000 gallons a year.
What if I cannot tell what brand the faucet is?
Common on older and builder-grade faucets. Pull the part and photograph it next to the handle and trim. A specialist can identify it from the photo, which is how we handle faucets with no visible brand or model number.