How to Fix a Leaking Tap: Washer and Cartridge Replacement Guide

To fix a leaking tap, turn off the water supply, remove the handle, replace the worn washer, ceramic cartridge or O-ring with an identical part, then put everything back and test it. A tap that only stops dripping when you crank the handle needs a new part, not a harder twist.

A tap that drips through the night is hard to ignore. You close it properly, you still hear it, so you go back and tighten it a bit more. That rarely helps, and it usually wears the part out faster.

The good news is that how to fix a leaking tap has a short answer. Nearly every leak comes down to one small part inside the tap, and replacing it takes under an hour with a screwdriver and an adjustable spanner. You can fix a leaking tap without a plumber if you work slowly and match the new part to the old one. This guide covers the causes, how to find the leak, the steps for each type of tap, what it costs in India, and when a new tap makes more sense.

Why Is Your Tap Leaking?

Every tap does one job when you close it: it seals the water in. A rubber washer or a pair of ceramic discs does that sealing, and when it wears out, water slips past. That’s a dripping tap. Four things cause it most of the time.

Worn tap washer

Older pillar taps and bib cocks close by pressing a rubber tap washer against a metal seat. Rubber hardens and cracks with age. Once it stops sitting flat, water seeps through even with the handle fully closed. If your tap takes a few full turns to open and close, this is most likely your problem.

Damaged ceramic cartridge

Single lever mixers, quarter turn taps and half turn taps don’t use a washer. Inside is a ceramic cartridge with two polished discs that slide over each other. A grain of sand or a little scale between them leaves a gap, and the tap drips. Cartridges can also crack with age or rough use.

Worn O-ring or loose tap spindle

Most hardware shops call the internal assembly the tap spindle. A small rubber O-ring around it keeps water from climbing up the stem. When the O-ring goes soft or flat, water leaks from under the handle.

Hard water and scale

If your area has hard water, minerals build up on washers, seats and ceramic discs. The scale scratches the sealing surfaces and wears them out faster. It’s the reason a tap only a couple of years old can start leaking.

Find Where the Tap Is Leaking First

Before you take anything apart, work out where the water is coming from. It saves you from buying the wrong part.

Tap leaking from the spout

This is the classic drip. Water keeps coming out of the outlet after the tap is closed. A tap leaking from the spout means the washer or the cartridge isn’t sealing any more.

Tap leaking from the handle

Water seeping around or under the handle, usually while the tap is running, points to the O-ring or the packing around the spindle. A tap leaking from the handle is often the easiest repair of all.

Tap leaking from the base

Water pooling where the tap meets the basin or the wall means a loose mounting nut, a tired gasket, or a threaded joint with no sealing tape. A tap leaking from the base usually needs tightening, not new internals.

Where it leaks	Likely cause	Fix
Spout, after closing	Worn washer or cartridge	Replace the washer or cartridge
Under the handle	Worn O-ring or packing	Replace the O-ring
Base of the tap	Loose nut, old gasket, no sealing tape	Tighten, replace the gasket, add PTFE tape
Under the basin	Flexible hose or its rubber washer	Replace the hose or washer

Tools and Parts You Need

You don’t need a toolbox full of gear.

• A screwdriver and a small set of Allen keys
• An adjustable spanner (wrap the jaws in masking tape so the finish doesn’t get scratched)
• A new washer, ceramic cartridge or O-ring
• PTFE sealing tape
• Pliers and an old cloth

Carry the old part to the hardware shop. Matching by eye goes wrong more often than you’d think, since washers and cartridges come in different sizes (35 mm and 40 mm are common for mixer cartridges).

How to Fix a Leaking Tap Step by Step

Before you start

Turn off the water. Most bathrooms have an angle valve under the basin or a stop valve for the whole bathroom. Close it, then open the tap to let the leftover water run out. Stuff a cloth into the drain, because a screw dropped down the pipe is a bad way to end the job.

How to replace a tap washer

This applies to older multi-turn pillar taps and bib cocks.

1. Pop the small cap off the top of the handle (it’s often marked red and blue, or H and C) and undo the screw underneath.
2. Pull off the handle, then unscrew the cover.
3. Loosen the bonnet nut with the spanner while your other hand holds the tap body. If the body twists, you can crack the basin or strain the pipe behind the wall.
4. Lift out the spindle. The washer sits at the bottom, held by a small nut or pressed into place.
5. Fit a new washer of the same size and thickness, then run a finger over the metal seat it presses against. If the seat feels rough or pitted, a new washer won’t last long. The seat needs re-cutting, or the tap needs replacing.

How to replace a ceramic cartridge in a single lever mixer tap

Most leaks in a single lever mixer tap come from the cartridge. The first steps are the same: close the water supply, take off the small cap on the lever, undo the grub screw underneath, and lift the lever off. Remove the cover ring, then unscrew the collar that holds the cartridge and pull the old one straight up.

Put the old and new cartridges side by side. The height, the base holes and the width should all match. Drop the new one in the same way round, tighten the collar until it feels snug (not forced), and refit the lever.

Quarter turn taps and half turn taps work on the same idea. You unscrew the spindle that holds the ceramic discs and swap the whole piece, since it’s sold as one unit.

How to replace a worn O-ring

For a leak under the handle, take out the spindle as above. The O-ring sits near the top. Pick it off with a small screwdriver, fit one of the same size, and rub a little silicone grease on it so it seats smoothly. Don’t use engine oil.

Fixing a leak at the base

Tighten the mounting nut under the basin a little at a time. On wall taps, unscrew the tap, wrap PTFE tape around the thread four or five times, and refit it. If the rubber gasket under the base has gone flat, replace that too.

How to Test the Tap After the Repair

Put everything back in reverse order. Keep the tap closed, open the angle valve slowly, then open the tap for a few seconds so the air in the pipe can escape. Close it, dry the spout, the handle and the base, and hold a dry tissue under the spout for ten minutes. Check the next morning again. A slow drip that returns overnight needs another look.

What If the Tap Keeps Leaking After the Repair?

If your tap is still leaking after changing the washer, the seat is the usual culprit. The other common reasons are a wrong-size part, a collar that isn’t fully tightened, or scale on the discs. For scale, soak the cartridge or spindle in a mix of white vinegar and water for about half an hour, rinse it, and fit it back. Keep vinegar away from the outer finish of the tap. If it still drips, a plumber can re-cut the seat, or you can replace the tap.

Repair or Replace a Leaking Tap?

Repair it if the body is sound and only the inside has worn. Replace it when:

• the body is corroded or pitted
• the handle wobbles or the finish is peeling
• you’ve replaced the washer or cartridge twice within a year
• you can’t find a matching part

When you buy a new one, look for ISI marked taps, which meet the relevant Indian Standard, and check the warranty before you pay. Ours is explained on the Agmeco warranty page.

Cost of Fixing a Leaking Tap in India: DIY vs Plumber

Parts are cheap. These are rough ranges at hardware shops, and they change with brand, size and city.

Part	Approximate price
Rubber washer	Not mention
Ceramic cartridge for a mixer tap	Not mention
Complete tap spindle	Not mention

The cost of fixing a leaking tap is mostly the plumber’s time, not the part. A washer or O-ring job costs almost nothing if you do it yourself. If you call a plumber, you’ll pay a visit charge on top of the part, and rates differ a lot between cities, so ask before he starts. For a cartridge you can’t get out, paying for help is reasonable.

How to Prevent Tap Leakage

Preventing tap leakage is mostly about small habits.

• Close taps gently. Forcing the handle crushes washers and chips ceramic discs.
• After plumbing work or tank cleaning, run the taps with the aerator removed so sand flushes out. Grit is what kills cartridges.
• Descale now and then, especially in hard water areas. Our tips to maintain your bathroom fittings cover cleaning without damaging the finish.
• Use a good-quality washer or cartridge when you replace one. Cheap rubber hardens quickly.
• Don’t ignore a small drip. Water slipping through a closed seat slowly cuts into it, and a ₹20 fix today can turn into a new tap later.

How Much Water Does a Dripping Tap Waste?

A drip looks small, but it never stops. Here’s an easy test. Put a measuring jug or a bottle under the dripping tap for ten minutes. Say it collects 100 ml. Multiply by 6 and you get 600 ml an hour. Multiply that by 24 and it’s a little over 14 litres a day, which is more than 5,000 litres a year from one tap.

Your own number will be different, but it’s usually bigger than people expect. That’s real water wastage, and it shows up on the bill if you pay for water. If you want to cut usage across the whole house, our list of water-saving taps is a good place to start.

Frequently Asked Questions Related to How to Fix a Leaking Tap

Final Thoughts

Once you know how to stop a dripping tap, it stops being a big job. Find where it leaks, match the part, replace it, and test it properly. If the tap has had its time, have a look at our range of bathroom taps, or get in touch and we’ll help you pick one.