How to Fix a Leaky Faucet

A dripping faucet is one of the most annoying sounds in a home, and it is also one of the most wasteful. A tap that drips once a second can waste thousands of litres of water over a year, and every drip is money going down the drain. The good news is that almost every faucet repair comes down to one inexpensive part — a washer, a cartridge, or a set of seals — and the job is well within the reach of a beginner with basic tools.

The trick is working out which type of faucet you have before you buy anything, because the repair is different for each design. This guide shows you how to diagnose the leak, identify your faucet type, and fix each of the four common designs step by step, plus when to stop and call a plumber instead. For more practical home fixes, visit our Home Improvement guides.

Why Faucets Leak

A faucet is a valve, and like any valve it relies on seals to hold back water pressure. Every time you turn a tap on and off, those seals wear a little. Over months and years, a rubber washer hardens and cracks, an O-ring flattens, or a cartridge wears out — and water starts to sneak past. Hard water makes the problem worse, because mineral deposits build up on the seals and the valve seat, the surface the seal presses against.

The leak itself is rarely an emergency, but it should not be ignored. Besides the wasted water, a constant drip can stain the sink and the basin, and a leak at the base of the faucet can rot the worktop or the cabinet underneath without you noticing. A faucet controls the flow of water through a valve, and understanding that simple mechanism is the key to fixing it: find the seal that has failed, and replace it.

Tools and Parts You Will Need

Most faucet repairs need only a few basic tools: an adjustable wrench, a Phillips and a flathead screwdriver, an Allen key set, a pair of pliers, plumber’s tape, a cloth or towel, and a small container to keep the parts in order. Helpful extras include penetrating oil for a stuck nut, a seat wrench for compression faucets, and plumber’s silicone grease for new O-rings — never use petroleum jelly on rubber seals, because it degrades the rubber over time.

For parts, buy the repair parts only after you know your faucet type and, ideally, its brand and model. Cartridges are not one-size-fits-all: different brands and models use different cartridges, so take the old one with you to the hardware store to get an exact match. Washer assortments are cheap and handy to keep in a drawer. Ball faucet repair kits — springs, seats and O-rings sold together — are the sensible buy for ball faucets, because the parts are small and it is not worth doing the job twice.

Step 1: Shut Off the Water and Plug the Drain

Before you take anything apart, turn off the water. Underneath most sinks you will see two valves, one for hot water and one for cold. Turn both of them clockwise until they are tight, then open the faucet to confirm the flow has stopped and to release the pressure. If either valve is stuck, leaks when you turn it, or does not shut the water off completely, stop there — in an older home you may need to use the main shutoff for the house, and if you do not know where it is or cannot operate it safely, call a plumber.

Next, plug the drain and cover the sink. Every faucet contains at least one small screw or spring that will find the drain opening if you give it the chance, and this is the step people skip and regret. Lay the parts out in the order they come off, and take a photograph at each stage — reassembly is where most faucet repairs go wrong, and a photo costs nothing.

Step 2: Work Out Where the Water Is Coming From

Two questions solve almost every faucet leak. First, where exactly is the water coming from? Dry the whole fixture, then run the tap and watch. Water dripping from the spout while the faucet is off means the valve seal has failed — the cartridge, the ball assembly, the disc, or a compression washer. A leak from the base of the spout usually means a worn O-ring, and a leak from the handle means the packing or a bonnet washer has gone.

People routinely replace a cartridge when the actual failure was a two-cent O-ring, so this diagnosis step saves you money and a wasted trip. Knowing where the water escapes also tells you which part to inspect first once the handle is off.

Step 3: Identify Your Faucet Type

There are four common faucet designs, and you can usually tell them apart from the outside. A compression faucet has two separate handles that you keep turning the harder you turn them, with a definite stop — these are common in older homes. A cartridge faucet has a single handle that lifts and swivels, or two handles that turn smoothly through about a quarter turn with no gradual tightening; it is the most common design in modern homes.

A ball faucet has a single handle sitting on a rounded cap over a domed body, common on older kitchen faucets. A ceramic disc faucet has a single lever over a wide cylindrical body and feels solid and precise when you move it; it is very long-lived, and when it does leak it is usually the inlet seals, not the discs themselves. For a fuller picture of how taps work, see the Wikipedia article on plumbing, which covers the fittings and valves used in household water systems.

Fixing a Compression Faucet

Compression faucets are common in older homes, and they drip when their rubber washers wear out — this is the cheapest repair of the lot. Pry off the decorative cap on the handle, unscrew the handle screw, and lift the handle off. Use an adjustable wrench to loosen and remove the packing nut beneath the handle, then pull out the stem. At the bottom of the stem you will find a small rubber seat washer held in place by a screw.

If the washer is worn, cracked, hardened or misshapen, replace it with the same size, and apply a light coating of plumber’s grease if the manufacturer recommends it. While you are there, check the O-ring on the stem: if it is cracked, stiff or misshapen, replace it too. Then inspect the valve seat inside the faucet body — the surface the washer presses against. If it is pitted or rough, it will wear through a new washer quickly; a plumber can resurface or replace a damaged seat. Reassemble in reverse order and avoid overtightening the packing nut, which damages threads and makes the handle stiff to turn.

Fixing a Cartridge Faucet

On a cartridge faucet, a leak is usually a faulty cartridge, not a washer. Remove the handle the same way — cap off, screw out, handle off — and you will see a metal or plastic retaining nut holding the cartridge in place. Loosen it with your adjustable wrench and pull the cartridge straight out. Some cartridges are held by a small clip rather than a nut, so look carefully and keep the clip safe.

Take the old cartridge to the store to get an exact replacement, because different brands and models have different cartridges. Note the orientation of the old cartridge before you remove it — most have a notch or a flat side that must line up the same way — and take a photo. Slide the new cartridge in, tighten the retaining nut, reattach the handle, and test. If the faucet still drips, the cartridge may be seated slightly wrong, or the O-rings on the cartridge body may need replacing.

Fixing a Ball Faucet

Ball faucets are a little trickier, but still manageable. These are the single-handle faucets where moving the handle forward and back controls temperature and left and right controls flow. The leak is usually a worn-out rubber seal or O-ring around the ball. Remove the handle — you may need an Allen key for a hidden set screw — then take off the cap, the cam and the packing, and lift out the ball itself.

Under the ball you will find two small rubber seats with a spring under each one. Replace the seats, springs and O-rings as a set, using a repair kit made for your faucet’s brand. Use plumber’s silicone grease on the new O-rings, reassemble in order, and hand-tighten the cap plus a small nudge with your wrench — overtightening cracks plastic and distorts new seals. If the ball itself is pitted or corroded, replace it too; a rough ball will chew through new seals quickly.

Fixing a Ceramic Disc Faucet

Ceramic disc faucets are the most durable of the four designs, and leaks are uncommon. When they do leak, it is usually the inlet seals at the bottom of the cartridge, sticky mineral buildup, or a damaged cartridge. Remove the handle and the decorative cap, then loosen the retaining nut or screws and lift the cartridge out. Clean any mineral deposits from the cartridge and the housing with white vinegar and a soft brush, and inspect the seals at the base of the cartridge.

If the seals are worn, replace them. If the cartridge itself is cracked or the ceramic discs are chipped, replace the whole cartridge — these are sold as a single unit for your faucet’s brand. A ceramic disc cartridge is a precision part, so handle it gently and do not force it; it should drop into place and sit flush before you tighten anything.

Reassemble and Test

Reassembly is the reverse of disassembly, in the order you laid the parts out. Use plumber’s silicone grease on new O-rings, hand-tight plus a nudge on nuts — never crank them down. Remove the plug from the drain, open the shutoff valves under the sink slowly, and run the faucet for a minute while you watch for leaks at the spout, the handle and the base. Fast water pressure can dislodge a new seal, so let the pressure build gradually.

Run both hot and cold, then turn the faucet off and wait a minute. If the spout stays dry and nothing weeps around the handle or the base, the repair is done. If it still drips from the spout, the valve seat may be damaged or the new part may be the wrong model — try reseating the part once, and if the leak persists, consider replacing the faucet or calling a professional.

When to Call a Plumber

Some situations are not DIY jobs. Call a plumber if the shutoff valves under the sink will not close or leak when you turn them, if the faucet is corroded solid and parts will not come apart, if you find a cracked faucet body, or if water is leaking inside the wall or under the floor — that last one is a bigger problem than a drip. Also call a professional if the same faucet keeps leaking after a repair, because the valve seat or the housing itself may be worn beyond a simple parts swap.

If you live in a rented home, a co-op or a flat with shared plumbing, check the rules first — you may need the building superintendent or landlord to shut off the water main, and some leases require a licensed plumber for any plumbing work. A plumber’s visit for a simple faucet repair is usually a short job, and it is far cheaper than the water damage a botched repair can cause. For other projects around the house, our Home Improvement guides can help you decide what to tackle yourself.

Frequently Asked Questions

How do I know what type of faucet I have?

Two handles that keep tightening are compression. A single handle that lifts and swivels, or two handles that turn smoothly through a quarter turn, is a cartridge faucet. A single handle on a rounded, domed cap is a ball faucet. A single lever over a wide cylindrical body that moves with a solid, precise feel is a ceramic disc faucet.

Can I fix a leaky faucet without turning off the water?

No — do not try it. Opening a faucet with the water on will flood the area and can damage the valve. Always close the shutoff valves under the sink first, open the faucet to confirm the water has stopped, and plug the drain before you take anything apart.

How long does a faucet repair take?

A straightforward washer or cartridge swap takes 30 minutes to an hour, including the trip to the hardware store. A ball faucet repair with a kit takes a little longer. Budget extra time the first time you do it, and take photos as you disassemble.

Why is my faucet still dripping after I replaced the washer?

The valve seat is probably pitted or corroded. A rough seat wears through a new washer quickly. A seat wrench can resurface or replace a removable seat on a compression faucet; otherwise, the faucet body may be worn out and the whole faucet may need replacing.

Is a dripping faucet wasting much water?

Yes. A tap dripping once a second can waste thousands of litres over a year, and a leak at the base can damage the worktop or cabinet below. Fixing a drip is one of the cheapest ways to cut water waste in your home.

For more background on the valves and fittings in your home’s water system, the Wikipedia article on taps explains the different valve designs in detail.

Tom Harris

Tom Harris writes Homeyo's home improvement guides, covering repairs, renovations and the jobs worth tackling yourself. He has spent more than fifteen years working around homes and writing about practical DIY, and he knows which jobs are simple and which need a professional. His guides give you honest costs, clear steps and the confidence to get started.