How to Fix a Leaky Kitchen Tap at Home

A dripping kitchen tap can waste water and leave mineral deposits around the sink. In many cases, the cause is a worn washer, O-ring, or cartridge; loose fittings or debris can also cause leaks. Before starting, check that you can reach the shutoff valves under the sink and identify your tap type. If the leak is coming from a supply hose, the shutoff valve, or inside a wall, the repair may be different from replacing a tap seal.

What You’ll Need

Adjustable wrench or the correct-size open-end wrench
Screwdrivers, usually Phillips and flat-head
Replacement washer, O-ring, or cartridge that matches the tap model
Small bowl or cup to catch water
Cloth or towel, plus a soft cloth to protect the tap finish
Flashlight and, if needed, needle-nose pliers
Optional: plumber’s silicone grease approved for potable-water fittings

Take a photo of the tap and any visible brand or model markings before buying parts. Tap designs vary, so do not assume a generic washer or cartridge will fit.

Step-by-Step

Identify the leak. Dry the tap and surrounding sink, then run the water briefly. Note whether it drips from the spout when the tap is off, leaks around a handle while water runs, or appears at the base or under the sink. This points to different likely causes. A puddle below the sink may come from a supply connection rather than the tap’s internal seals.
Shut off the water supply. Turn the hot- and cold-water shutoff valves beneath the sink clockwise until they stop; do not force a stiff valve. If there are no working local valves, shut off the home’s main water supply. Open the tap to release pressure and drain remaining water. If water continues flowing, stop and confirm the correct supply is off before taking anything apart.
Protect the sink and close the drain. Put a towel in the sink and cover the drain opening so a small screw cannot disappear down it. Set a bowl nearby for parts and trapped water. Keep track of each component’s order and orientation; a quick photo at each stage can help with reassembly.
Remove the handle. Look for a small cap or plug on the handle and carefully lift it with a fingernail or small flat screwdriver. Remove the screw beneath it, then lift off the handle. Some taps use a set screw hidden at the side or rear, often loosened with an Allen key. Avoid levering hard against the finish. If the handle is stuck, use gentle movement rather than force that could crack it.
Expose the valve parts. Depending on the design, remove a decorative cap, retaining nut, clip, or bonnet to reach the cartridge or valve stem. Wrap a cloth around metal parts before using a wrench to prevent scratches. Turn threaded parts carefully; some fittings use reverse or unusual arrangements, so stop if a part will not move with reasonable pressure and check the tap’s instructions.
Remove and inspect the worn part. Pull the cartridge or stem straight out if the design allows, noting its alignment. For a compression tap, inspect the small rubber washer at the end of the stem and the O-ring around the stem. For a single-handle cartridge tap, inspect the cartridge and its seals. Look for cracks, flattening, hardening, mineral buildup, or grit. Do not scratch the valve seat or force a cartridge sideways.
Match and install the replacement. Take the old part to a plumbing-supply store or use the tap’s model information to find an exact match. Clean loose debris from the accessible opening with a soft cloth. Fit the replacement in the same orientation as the original. Apply only a thin film of potable-water-safe silicone grease to suitable O-rings if the maker recommends it; do not use petroleum jelly, which can damage some rubber seals.
Reassemble the tap. Refit the retaining clip, nut, cap, and handle in reverse order. Tighten threaded fittings snugly, not excessively: overtightening can damage threads, seals, or plastic parts. Confirm the handle moves normally and that all components sit evenly.
Restore water and check. Close the tap, then slowly turn the shutoff valves counterclockwise. Watch the area under the sink for leaks as the lines pressurize. Run both hot and cold water, then turn the tap off and check the spout, handle, and base again. Dry the area and recheck after several minutes; a leak may be easier to spot on a dry surface.

Common Mistakes

Skipping the shutoff: Removing a valve part with the water on can cause uncontrolled flow. Verify the supply is off by opening the tap before disassembly.
Buying a part by appearance alone: Similar-looking cartridges can differ in length, slots, and alignment. Match the model or compare the old part directly.
Overtightening: A wrench can crush washers or damage plastic threads. Tighten only enough to seat the parts and stop leaks.
Mixing up orientation: Reversing a cartridge or stem can affect flow or prevent the handle from closing properly. Take photos and note alignment.
Assuming every drip needs a washer: Many modern taps use cartridges, while a leak under the sink may come from a hose or connection. Locate the source first.

Tips

Make sure the replacement is designed for your exact tap model; manufacturer instructions take priority over generic guidance.
If the shutoff valves are corroded, seized, or begin leaking when turned, do not force them. A plumber can replace or repair them safely.
Clean visible mineral deposits gently. Avoid sharp tools that can gouge the valve seat or damage the tap’s finish.
If the leak is at a threaded hose connection, check whether its washer is damaged and whether the connection is properly seated. Do not apply thread tape to a fitting that seals with a rubber washer unless the manufacturer calls for it.

Troubleshooting

The tap still drips from the spout: The replacement may be the wrong type, installed backward, or not seated fully. Shut off the water again and check alignment and seals. On a compression tap, a damaged valve seat can let water pass even with a new washer; that may need a special seat tool or professional repair.

Water leaks around the handle: Check the stem O-ring or cartridge seals, and confirm the retaining nut is properly seated. Do not simply tighten the nut hard; replace damaged seals or the cartridge if needed.

The tap leaks underneath: Dry the hoses and connections, then run water and watch for the first wet spot. If a hose is split, corroded, or leaking at its crimp, replace it with a compatible supply line. If a shutoff valve itself leaks, stop and get help rather than continuing to turn it.

Flow is weak after reassembly: Debris may have shifted into the aerator or cartridge. Turn off the water, remove and rinse the aerator if accessible, and check that the cartridge is correctly seated. If flow remains poor or you cannot identify the cause, consult the tap maker or a plumber.

A part will not come loose: Mineral buildup or corrosion may have seized it. Avoid hammering or applying excessive force, which can break the tap or damage plumbing. Use the manufacturer’s removal instructions or call a plumber.

Frequently Asked Questions

Why does a kitchen tap drip when it is turned off?

A worn washer, damaged cartridge, or debris around the valve is a common cause. The exact repair depends on the tap design and the location of the leak.

Can I fix a leaky tap without shutting off the water?

No. Shut off both supply valves under the sink, or the main supply if necessary, and open the tap to release pressure before taking it apart.

How do I know whether my tap uses a cartridge or a washer?

Two-handle compression taps commonly use washers, while many single-handle taps use a cartridge. Designs vary, so check the model information or inspect the parts after shutting off the water.

Should I replace both hot and cold cartridges?

Follow the tap manufacturer’s guidance. If both sides use matching parts and are similarly worn, replacing both can be practical, but a failed seal does not automatically mean both need replacement.

When should I call a plumber?

Call a plumber if shutoff valves are stuck or leaking, a valve seat is damaged, parts are badly corroded, or the leak is inside a wall or cannot be isolated. Also stop if the repair would require force that could damage the plumbing.

Further reading: U.S. Environmental Protection Agency. Details can change, so check the official page for anything that matters to you. Spotted a mistake? Tell us. How we write an answer.