Faucet Won't Stop Dripping? Here's the #1 Cause (and the 15-Minute Fix)
You tighten the handle as hard as you can, but the drip, drip, drip continues — all day, all night, running up your water bill one drop at a time. Before you call a plumber for a $200 visit or start shopping for a new faucet, check one thing first. It fixes this problem more often than anything else — and the replacement part costs less than a sandwich.
Why This Happens
Inside every faucet handle is a cartridge, valve stem, or compression assembly that controls water flow. When you turn the handle off, a rubber washer, ceramic disc, or cartridge seal presses against a metal seat, creating a watertight barrier that stops the flow. Over years of use — and especially in areas with hard water — that seal wears down. The rubber hardens and cracks. The ceramic disc develops micro-scratches. Mineral deposits build up on the metal seat, preventing a perfect seal.
Once the seal is compromised, water seeps through even when the handle is fully closed. The drip starts slowly — one every few seconds — and gradually worsens as the damage spreads. A single faucet dripping once per second wastes over 3,000 gallons per year. The good news: the internal cartridge or washer is designed to be a wear item, meant to be replaced long before the faucet itself needs replacement. This single issue is responsible for more dripping faucets than any other cause, and swapping the cartridge is a straightforward job that requires only an adjustable wrench and a screwdriver.
Signs You're Dealing With This
- The faucet drips steadily even when the handle is turned off completely
- Tightening the handle harder temporarily slows the drip, but it always returns
- The drip is worse on the hot side, or only one handle drips while the other doesn't
- You live in a hard-water area and the faucet is more than 3 years old
- The handle feels gritty, stiff, or requires extra force to turn off fully
- Water pools around the base of the faucet or stains the sink basin
The Fix, Step by Step
- Turn off the water supply. Look under the sink for two small oval shutoff valves — one for hot, one for cold. Turn both clockwise until firm. If the valves are stuck or missing, shut off the main water supply to the house.
- Plug the sink drain. Drop a rag over the drain or use a stopper. Small parts — screws, clips, washers — love to disappear down the drain the moment you look away.
- Remove the faucet handle. Most handles have a small plastic cap (often labeled "H" or "C" or colored red/blue) on top or in front. Pry it off gently with a flathead screwdriver to reveal a screw. Remove the screw and pull the handle straight up. If it's stuck from mineral buildup, wiggle it side to side — don't hammer it.
- Remove the decorative escutcheon or retaining nut. Under the handle you'll see a metal or plastic sleeve, collar, or bonnet nut. Unscrew it counterclockwise with an adjustable wrench. Wrap the wrench jaws in tape if you're worried about scratching the finish.
- Pull out the cartridge or valve stem. This is the cylindrical brass or plastic component at the center. It may slide straight out, or you may need to grip the stem with pliers and pull firmly. Some cartridges require a special puller tool (about $15 at hardware stores), but most come out by hand or with gentle persuasion. Note the orientation — it must go back in the same way.
- Take the old cartridge to the hardware store. Match it exactly, or use the faucet brand and model number. Cartridges are not universal. Common brands (Moen, Delta, Kohler, Pfister) each have proprietary designs. A store employee can help you find the exact match. Cost is $5 to $25.
- Install the new cartridge. Apply a thin layer of plumber's grease (included with some cartridges, or $3 at the store) to the rubber O-rings on the new cartridge. This prevents tearing during insertion and makes future removal easier. Slide it into the valve body in the exact same orientation as the old one.
- Reinstall the retaining nut, escutcheon, and handle. Hand-tighten everything first, then snug with the wrench. Don't over-torque — brass threads strip easily.
- Turn the water back on slowly. Open the shutoff valves counterclockwise gradually. A sudden rush of pressure can damage the new cartridge. Test both hot and cold handles. The drip should be completely gone.
When to Call a Professional Instead
If you've replaced the cartridge, cleaned the seat, and the faucet still drips, the issue may be a cracked valve body, damaged supply lines, or corrosion inside the wall pipe. A plumber can inspect the valve body with a borescope and replace the entire faucet if the internal passages are compromised. Also call a pro if the shutoff valves under the sink are frozen or leaking — replacing those requires soldering or compression fittings that are best left to someone with experience.
Quick Questions
How long does a faucet cartridge last?
3 to 10 years, depending on water hardness and usage frequency. Hard water with high mineral content wears cartridges out faster. A whole-house water softener can double the lifespan of every faucet in your home.
Can I just tighten the packing nut instead of replacing the cartridge?
Tightening the packing nut (the nut around the stem) stops leaks from the handle area, not the spout. A spout drip requires a new cartridge or washer. Tightening the wrong nut can crack the housing.
Why does my faucet drip only at certain times of day?
Water pressure fluctuations from municipal supply or from neighbors' usage can force water past a marginal seal. The cartridge is still worn — the pressure just exposes it intermittently. Replace it before it fails completely.
Is it cheaper to replace the whole faucet?
For basic faucets under $50, a full replacement is sometimes cost-competitive with buying a cartridge and spending the time to swap it. But for quality faucets ($150+), a $15 cartridge replacement is always the smarter financial choice. And you avoid the hassle of disconnecting supply lines and reinstalling the entire fixture.
Still dripping after trying this? Check out our guide on faucet valve seats and compression washer replacement — the next most common cause for older faucets.