A dripping faucet can waste thousands of gallons a year and is usually caused by a worn part costing a few dollars. For most faucets this is a genuinely beginner-friendly repair — here’s exactly how to do it.
Key takeaways
- Almost all drips come from one worn part — a washer, O-ring or cartridge.
- Turn off the water supply first, and plug the drain before you remove anything.
- Identify your faucet type before buying parts; take the old part to the store to match it.
- Lay parts out in the order you remove them — reassembly is just the reverse.
Why faucets leak in the first place
Inside every faucet, a small component presses against a seat to form a watertight seal when you turn the handle off. That component is under pressure and friction every time you use it, and rubber and plastic parts eventually harden, crack or wear thin.
Where the drip appears tells you a lot. Water dripping from the spout usually means a worn washer, seal or cartridge. Water seeping around the base of the handle usually points to a failed O-ring. Mineral buildup from hard water accelerates all of it.
What you’ll need
- Adjustable wrench and/or a set of screwdrivers (flathead and Phillips)
- Allen key set — many modern handles use a small hex screw
- Replacement washers, O-rings or a cartridge to match your faucet
- Plumber’s grease (silicone-based)
- White vinegar and an old toothbrush for mineral deposits
- A towel and a small container for parts
Identify your faucet type first
This determines which part you need. There are four common types:
- Compression — two separate handles for hot and cold, and the handle tightens noticeably as you close it. Older design; uses rubber washers.
- Cartridge — single or double handle that turns smoothly without tightening. Fixed by swapping the cartridge.
- Ball — single handle that moves in a rounded, swivelling motion, common on kitchen sinks. Repaired with a ball-type kit.
- Ceramic disc — single lever over a wide cylindrical body. Very durable; usually needs seals cleaned or replaced rather than the whole unit.
If you’re unsure, photograph the faucet and take the old part with you to the hardware store — matching physically beats guessing from a description.
Step-by-step: fixing the leak
- Turn off the water supplyLook under the sink for two shutoff valves and turn them clockwise until closed. If there are none, or they won’t budge, shut off your home’s main water valve. Then open the faucet to release remaining pressure and confirm the flow has stopped.
- Plug the drain and lay a towelA sink stopper or rag in the drain prevents small screws and clips from disappearing. The towel protects the basin and gives you a surface to lay parts on in order.
- Remove the handlePry off the decorative cap on top with a flathead screwdriver to expose the screw, or locate the small hex screw at the base or side. Undo it and lift the handle off. If it’s stuck from mineral buildup, wrap it in a vinegar-soaked cloth for 15 minutes rather than yanking.
- Take out the working partYou’ll find either a packing nut and stem (compression), a retaining clip and cartridge, or a ball assembly. Loosen the nut with your wrench and pull the component straight up. Keep everything in the order it came out.
- Find and replace the worn partInspect the rubber washer, O-rings and seals for flattening, cracking or tearing — the culprit is usually obvious. Replace with an exact match. If the faucet is old or the cartridge is scored, replacing the whole cartridge is more reliable than chasing individual seals.
- Clean the seat and threadsWipe out grit and soak mineral deposits with white vinegar, scrubbing gently with a toothbrush. A rough or crusted valve seat will chew through a brand-new washer within weeks.
- Grease and reassembleApply a thin coat of silicone plumber’s grease to new O-rings, then rebuild in reverse order. Tighten firmly but don’t crank — overtightening deforms new seals and causes the leak to return.
- Turn the water back on slowly and testOpen the shutoff valves gradually to avoid a pressure surge. Run hot and cold, then check underneath with a dry hand or paper towel for any seepage. Watch it again after a few hours.
The terms, explained
- Cartridge
- The removable insert inside many modern faucets that controls water flow and temperature. Usually replaced as a whole unit.
- O-ring
- A small rubber ring that seals joints. A failed O-ring typically causes leaking around the handle base rather than the spout.
- Washer
- A flat rubber disc in compression faucets that presses against the valve seat to stop flow. The classic cause of a dripping spout.
- Valve seat
- The metal surface the washer presses against. If it’s corroded or scaled, new washers wear out quickly.
- Packing nut
- The nut holding the stem assembly in place, which must be loosened before removing the internals.
- Plumber’s grease
- Silicone-based lubricant safe for rubber seals. Petroleum jelly is not a substitute — it degrades rubber over time.
When to call a plumber instead
- The shutoff valves are seized or leaking themselves
- Pipes are visibly corroded, or you find water damage in the cabinet
- The leak continues after replacing seals and the cartridge
- You have low water pressure throughout the house, suggesting a bigger issue
- Anything requires cutting, soldering or altering the pipework
Frequently asked questions
How much water does a dripping faucet really waste?
The US EPA estimates a faucet dripping once per second wastes over 3,000 gallons a year — roughly the water needed for 180 showers. Fixing it usually pays for itself quickly.
Why is my faucet still dripping after I replaced the washer?
Most often the valve seat is corroded or scaled, so the new washer can’t seal properly. Clean or resurface the seat — or replace the cartridge entirely. Overtightening during reassembly is the other common cause.
Do I need to turn off the water to the whole house?
Usually not. Most sinks have local shutoff valves underneath. Only use the main shutoff if those are missing or won’t close.
Should I repair or just replace the faucet?
If the body is sound and parts are available, repair is far cheaper. Consider replacing if the faucet is very old, parts are discontinued, or the body itself is cracked or heavily corroded.
