How to Repair Leaky Bathroom Faucet: A Step-by-Step Guide for Beginners

Updated November 2026

Most leaky bathroom faucets can be fixed in under an hour with basic hand tools and a replacement cartridge or washer. This guide walks you through how to repair a leaky bathroom faucet, from shutting off the water to testing your work. You will also learn how to tell which part has failed so you buy the right replacement the first time.

Shut Off the Water and Identify the Faucet Type

Close the shutoff valves under the sink, then open the faucet to drain the remaining water. Plug the sink drain so small parts don’t disappear down it. Next, identify your faucet type, because it determines which part is failing:

Shopping for one? See our guide: Bathroom Leaky Faucet Repair Kits: 7 Best Picks Compared (2026).

• Compression faucets have separate hot and cold handles and use rubber washers that wear out over time.
• Cartridge faucets use a single cylinder inside one handle or two handles and leak when the cartridge seals wear.
• Ball faucets have one dome-shaped handle and a slotted ball that leaks when springs and seals degrade.
• Ceramic disc faucets use two ceramic discs; leaks usually come from grit or worn rubber seals.

Disassemble the Faucet and Find the Worn Part

Pry off the decorative cap on the handle, then remove the handle screw with a Phillips or Allen wrench depending on the model. Unscrew the packing nut or retaining nut and lift out the stem, cartridge, ball or disc assembly. Take the old part to the hardware store or photograph it so you can match it exactly.

Common Worn Components to Look For

1. Check rubber washers and O-rings for flattening, cracks or hardened edges.
2. Inspect the valve seat at the base of the faucet for pitting or mineral buildup.
3. Look at the cartridge or disc for scratches, chips or debris trapped in the seals.

Replace the Faucet Parts and Reassemble

Install new washers, O-rings, or the complete cartridge that matches your model. Apply plumber’s grease to new O-rings so they seat smoothly and don’t tear. Reassemble in the reverse order, tightening screws firmly but not forcing them, since overtightening cracks plastic parts and damages seals.

Test the Repair and Confirm the Leak Is Gone

Open the shutoff valves slowly to avoid a sudden pressure surge. Run the faucet on hot and cold, then turn it off and watch the spout for at least a minute. A slow drip usually means a seal is not fully seated or a valve seat needs cleaning or replacement.

Symptom	Likely cause	Fix
Drip from spout when off	Worn washer or cartridge	Replace the seal or cartridge
Leak at handle base	Failed O-ring or packing nut	Replace the O-ring and tighten the nut
Hard to turn handle	Mineral buildup or worn stem	Clean or replace the stem

If you’re working with a specific brand, a model-specific kit is often the simplest option. For example, Bathroom Faucet Repair Kits: How to Fix a Leaky Faucet in 6 Steps explains how kits match common parts, and Repair Dripping Faucet Bathroom: A Step-by-Step Guide for Beginners covers the same steps for other styles.

Recommended gear

A basic set of tools makes disassembly easier and reduces the chance of scratching finishes.

• Adjustable wrench helps loosen packing nuts without rounding them off. View on Amazon
• Plumber’s grease keeps new O-rings lubricated and helps them seal. View on Amazon
• Faucet repair kit bundles common washers and seals for many brands. View on Amazon

Common Mistakes and Tips

• Forgetting to shut off the water supply before starting, which leads to a flooded vanity.
• Buying a generic washer without checking the brand, since many faucets use proprietary cartridges.
• Overtightening handle screws, which can crack the handle or strip the threads.
• Skipping the valve seat inspection, so a new cartridge still leaks.
• Taking the old part apart without photographing it first, making reassembly harder.

FAQ

Do I need to replace the whole faucet to stop a leak?

Usually not. Most leaks come from a worn washer, O-ring, or cartridge, and replacing that part costs far less than a new faucet. Replace the whole unit only if the body is corroded or the valve seat is badly damaged.

How long does a bathroom faucet repair take?

Most homeowners finish a single-handle or two-handle repair within one hour once the parts are on hand. Allow extra time if mineral buildup has seized the stem or cartridge.

Can I repair a leaky faucet without shutting off the main water?

In most homes you only need the shutoff valves under the sink, which isolate the faucet. If those valves are old or don’t close fully, shut off the main supply or consult a licensed plumber before proceeding.

Conclusion

Once you identify the faucet type and the worn part, repairing a leaky bathroom faucet is a manageable weekend task. Keep the old parts for matching, use plumber’s grease on new seals, and test slowly after reassembly. If the leak returns or the valve seat is damaged, a licensed plumber can confirm the problem and recommend the right fix.

Related reading

• How to Replace a Bathroom Faucet: A Step-by-Step Guide for Beginners

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