To fix a leaking bathroom faucet, turn off the water at the small valves under the sink, take the handle apart, replace the worn cartridge, washer or O-ring, and put it back together. Match the replacement part to your faucet before you start.
Where the leak shows up tells you which part has failed. A drip from the spout points to the cartridge or seat, while water pooling around the base of the faucet usually means a bad O-ring. A leak under the sink often points to a supply line or valve.
This guide shows how to tell them apart, what you can do safely, and when a call is the better choice. If the faucet is beyond saving, see our page on faucet repair.
Most Westminster homes date to the 1960s and 1970s, with a median build year around 1971, so original angle stops under bathroom sinks are common. Test them before a repair, and know where your main shutoff is. City Water Division staff can be reached at (714) 894-3796 on weekdays for leaks and main issues.
Work out where the water is coming from
Dry the sink and the counter with a towel, then watch for a few minutes. A leak that appears only when the faucet is running points to a different part than one that drips constantly.
Also look under the sink with a flashlight. A wet cabinet floor could be a faucet leak running down the pipe, or it could be a drain or supply issue. Tissue pressed to each joint shows which one is actually wet.
| Where it leaks | Likely cause | Usual fix |
|---|---|---|
| Drips from the spout when off | Worn cartridge, washer or seat | Replace the cartridge or washer |
| Pools at the base of the spout | Worn O-ring | Replace the O-ring |
| Leaks around the handle | Loose packing nut or worn seal | Tighten or replace the seal |
| Wet only under the sink | Supply line or shutoff valve | Tighten, replace line or valve |
Shut off the water and protect the sink
Find the two small oval or round valves under the sink, called angle stops, and turn each clockwise until snug. Open the faucet to drain the remaining water and confirm the flow has stopped.
Put a towel in the sink basin to catch small screws and parts, and cover the drain opening. A dropped screw down the drain is a common reason a five minute job becomes an hour.
Before you take anything apart
- Angle stops turned fully clockwise
- Faucet opened to release pressure
- Drain plugged or covered with a towel
- Photos taken of the handle before disassembly
- Small container ready for screws
Identify your faucet type
A two-handle faucet usually has a cartridge or compression stem behind each handle. A single-handle faucet has one cartridge that controls both temperature and flow. Ball and disc designs are less common in bathrooms.
Take the old cartridge or washer to a hardware store so you can match it exactly. Brand matching matters, since cartridges that look alike can differ by a few millimeters and still fail to seal.
Replace the cartridge or washer step by step
Pop off the decorative cap on the handle and remove the screw underneath. Lift the handle off, then unscrew the retaining nut or clip holding the cartridge in place. Pull the cartridge straight up, rocking it gently if it resists.
Compare the new part to the old one before installing. Add a thin film of plumber's grease to the O-rings and seat the new cartridge firmly. Reassemble in reverse order, then open the angle stops slowly and test.
- 1
Remove the handle
Pop the cap, remove the screw and lift the handle off.
- 2
Pull the old cartridge
Remove the retaining nut and extract the cartridge straight up.
- 3
Install the new part
Grease the O-rings and press the new cartridge into place.
- 4
Reassemble and test
Replace the nut and handle, then open the valves slowly.
Fixing a base leak with a new O-ring
A pivoting or swivel spout sits on rubber O-rings that wear out over time. Water seeps past them and pools at the base of the faucet. The fix is cheap, often just a few dollars, and takes about twenty minutes.
Unscrew the spout, slide off the old O-rings and clean the groove with a damp cloth. Roll the new rings on, coat them with grease and slide the spout back down. If the metal body itself is pitted or corroded, a replacement faucet is the better long-term answer.
A steady drip adds up to a surprising amount of wasted water over a year. If you also notice a rising water bill, call about leak detection to rule out a hidden problem elsewhere in the home.
Why hard Westminster water speeds up faucet wear
The City of Westminster's 2024 Water Quality Report lists average hardness of 252 mg/L, roughly 14.7 grains per gallon. Hard water leaves mineral crust on cartridges, aerators and seats. That crust scratches rubber seals, which then drip.
Practical steps help. Unscrew the aerator every few months and soak it in vinegar, and wipe the faucet base dry to slow buildup. If scale shows up on every fixture, a water softener may be worth discussing.
Older Westminster bathrooms and stubborn valves
Westminster's median home was built around 1971, and many bathrooms still have their original shutoff valves. Old stops can seize or leak when turned. Move them gently, and if one will not close fully, stop and do not force it.
A stuck valve means you may need to shut the water at the main. If water will not stop, call the City Water Division at (714) 894-3796 during business hours, or phone our 24/7 line. For after-hours water emergencies in the city, the dispatch number is (714) 898-3315.
Tools and parts worth keeping in a drawer
Most faucet repairs need only a few basic items. Having them on hand turns a surprise drip into a short, calm job instead of a trip to the store with a dismantled faucet.
Buy the exact cartridge for your model once you have identified it, and keep spare O-rings in a labeled bag. Plumber's grease and Teflon tape cost little and last for years.
- Adjustable wrench and a set of small screwdrivers
- Hex keys for set screws under the handle
- Plumber's grease for O-rings
- Spare O-rings and washers in common sizes
- White vinegar and a soft brush for aerators
When to stop and call a plumber
Call if the angle stops will not close, if the faucet body is corroded, if the handle is stuck or if water is spraying. A damaged faucet body, or a leak that continues after a new cartridge, usually needs replacement, not repair.
We give a clear price before work starts and serve Westminster along with Garden Grove. See our service area page for nearby towns.
According to the City of Westminster's 2024 Water Quality Report, average hardness is 252 mg/L, a common cause of scale inside faucet cartridges. Replacement fixtures follow the California Plumbing Code (Title 24, Part 5).
Bathroom faucet leak questions from Westminster homeowners
Why is my bathroom faucet dripping when it is off?
A worn cartridge, washer or seat is the usual cause. Replacing the part normally stops the drip.
Can I fix a leaking faucet without turning off the main water?
Yes, if the angle stops under the sink close fully. Turn both off and open the faucet to confirm the flow stops.
How much does a leaking faucet repair cost?
Parts are often inexpensive, and a plumber visit varies with the faucet type and access. Ask for a clear price before work starts.
Does hard water in Westminster cause faucet leaks?
It contributes. Water at roughly 14.7 grains per gallon leaves scale that damages seals and cartridges. Cleaning aerators and wiping fixtures dry helps.
Should I repair or replace my old faucet?
Repair if the body is sound and parts are available. Replace if the finish is flaking, the body is corroded or leaks keep coming back.
Is a leaking faucet an emergency?
A slow drip can wait for a scheduled visit. Spraying water or a seized valve should be treated as urgent, and our phone line is answered 24/7.