How to Stop a Leaking Bathroom Faucet: A Step-by-Step Guide for Beginners

Updated November 2026

To stop a leaking bathroom faucet, you need to identify the type of faucet you have, shut off the water supply, and replace the worn part causing the drip. Most leaks come from a worn washer, O-ring, cartridge, or valve seat, and each one can be replaced with basic hand tools. This guide walks you through the process so you can fix the drip in an hour or so.

Identify Your Faucet Type

Before you buy any parts, you need to know which faucet design you have. The internal mechanism determines which replacement part you need, so this step matters more than any other.

• Compression faucets have separate hot and cold handles that turn several times to open. They use rubber washers and O-rings.
• Cartridge faucets usually have one handle that slides or rotates. Inside is a single cartridge that controls flow and temperature.
• Ball faucets have one handle on a rounded housing and use a slotted ball with several springs and seats.
• Ceramic disc faucets have a handle that moves in a smooth arc and use two ceramic discs inside.

If you’re unsure, remove the handle and look at the stem or cartridge. A quick photo at the hardware store can also help you match parts. For brand-specific guidance, see Moen Bathroom Faucet Remove Handle: Step-by-Step Guide (2026).

Shut Off the Water and Remove the Handle

Turn off the water at the shutoff valves under the sink. If the valves are stiff or do not close fully, shut off the main water supply to the house before you continue.

1. Open the faucet to drain remaining water and relieve pressure.
2. Pry off the decorative cap on the handle, usually with a flathead screwdriver.
3. Remove the handle screw, then lift the handle off the stem or cartridge.
4. Unscrew the packing nut or retaining nut that holds the stem or cartridge in place.

Place a towel in the sink basin and cover the drain. Small screws and springs can disappear quickly if they drop into the drain.

Replace the Worn Part That Causes the Leak

Once the internal parts are exposed, look for the component that is worn or damaged. Common culprits include:

• A cracked or flattened rubber washer on a compression stem
• A worn O-ring that no longer seals around the stem
• A damaged valve seat, which shows pitting or grooves
• A failing cartridge or ceramic disc with mineral buildup

Take the old part to the store or compare it with a replacement kit. Match size, shape and thread count exactly. Coat new O-rings with plumber’s grease before installing them, and reassemble in the reverse order you took them apart. Hand-tighten first, then give the nut a final quarter turn with a wrench. Overtightening can crack the body or damage new seals.

If the valve seat is pitted, a seat wrench can remove and replace it. Many faucet manufacturers sell repair kits that include the parts most likely to fail, which saves a second trip to the store. For a comparison of kits, see Bathroom Leaking Faucet Repair: 6 Best Repair Kits Compared (2026).

Test the Faucet and Check for Remaining Drips

Slowly turn the water supply back on at the shutoff valves. Open the faucet slowly and watch for drips or leaks around the base and handle. Run both hot and cold water, and test the handle in several positions.

If the drip continues, the most common reason is a seal that is not fully seated or a part that was installed backward. Shut off the water and reopen the assembly to check. If the faucet is a cartridge or ceramic disc design and still leaks after the replacement, the body itself may be cracked, and the faucet may need full replacement. For a related guide on tub-spout leaks, see Bathroom Tub Faucet Dripping: How to Find and Fix the Leak.

Recommended gear

• Faucet repair kit: Kits matched to your faucet brand include the O-rings, washers and springs most likely to fail, so you avoid guesswork. View on Amazon
• Plumber’s grease: A small tube keeps O-rings supple and helps them seal without tearing. View on Amazon
• Seat wrench set: Useful for removing stubborn valve seats without damaging the faucet body. View on Amazon

Common mistakes to avoid

• Buying parts before identifying the faucet brand and type, which leads to wrong-size washers and cartridges.
• Skipping the shutoff valves and relying on the faucet alone to stop the water.
• Overtightening the packing nut, which can crack the body or deform new seals.
• Forgetting to cover the drain, so small screws and springs fall out of reach.
• Reusing a worn O-ring because it looks intact. Compressed or hardened rubber often leaks after reassembly.

FAQ

Why does my bathroom faucet keep dripping after I replace the washer?

The new washer may be the wrong size, installed backward, or not seated fully in its groove. Check the fit and make sure the valve seat is not pitted, since a damaged seat will keep leaking even with new washers.

Do I need to turn off the main water supply to fix a leaking faucet?

Usually no, because the shutoff valves under the sink control water to the faucet. If those valves are stiff or leak, shut off the main supply to your home before you start.

When should I call a plumber instead of fixing the leak myself?

Call a licensed plumber if the faucet body is cracked, if you find corroded supply lines, or if the leak continues after you have replaced the internal parts. A professional can also help if you are unsure about gas, electrical or structural issues near the sink.

Conclusion

A leaking bathroom faucet is usually caused by one worn part, and you can often replace it in about an hour with basic tools. Identify your faucet type, shut off the water, and match the new part exactly before reassembly. Once the drip stops, check the faucet periodically so small leaks don’t turn into water damage.

Related reading

• Bathroom Faucet Is Leaking: How to Find and Fix the Drip Yourself
• Bathroom Faucet Is Dripping? How to Find and Stop the Leak
• How to Replace a Bathroom Faucet: A Step-by-Step Guide for Beginners

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