A dripping faucet wastes water, drives up your bill, and keeps you awake at night. The good news is that most faucet leaks are caused by worn-out internal parts that cost a few dollars and take 30 minutes to replace. You do not need a plumber for this repair — just basic tools and a trip to the hardware store.

How to Fix a Leaky Faucet

Before You Start

Turn off the water supply. Look under the sink for two shut-off valves (hot and cold). Turn them clockwise until they stop. If there are no shut-off valves under the sink, turn off the main water supply to the house.

Open the faucet to release remaining pressure and drain residual water.

Plug the drain with a rag or sink stopper so small parts do not fall in.

Have a set of hand tools ready: adjustable wrench, Phillips and flat screwdrivers, pliers, and a basin wrench if needed.

Identify Your Faucet Type

There are four main faucet types, each with a different internal mechanism:

Ball Faucet (Single Handle, Round Cap)

Common in kitchens. A single handle moves over a rotating ball that controls flow and temperature. Leaks usually come from worn O-rings, springs, or valve seats around the ball.

Repair: Buy a ball faucet repair kit (Delta, Peerless, or generic — about $8). Remove the handle by loosening the set screw under the handle or behind the decorative cap. Lift off the cap and packing nut. Remove the ball, springs, and rubber seats. Replace all parts from the kit and reassemble. Tighten the adjusting ring until the leak stops without making the handle stiff.

Cartridge Faucet (Single or Double Handle)

Used by Moen, Price Pfister, and others. A cylindrical cartridge moves up and down (or rotates) to control flow. Leaks come from a worn cartridge or O-rings.

Repair: Remove the handle (set screw, then handle), remove the retaining clip or nut, and pull the cartridge straight out with pliers. Take the old cartridge to the hardware store to find an exact match. Install the new cartridge and O-rings, reassemble, and test.

Ceramic Disc Faucet (Single Handle, Wide Base)

Modern and durable. Two ceramic discs slide against each other to control flow. These rarely leak, but when they do, it is usually due to damaged disc seals or a cracked disc.

Repair: Remove the handle, unscrew the disc cylinder cap, and lift out the cylinder. Replace the rubber seals on the bottom of the cylinder, or replace the entire cylinder if the ceramic is cracked. When turning water back on, open the faucet first and turn the supply on slowly — a sudden blast of water can crack the new ceramic discs.

Compression Faucet (Double Handle, Older Style)

The oldest design. Turning the handle screws a rubber washer down onto a valve seat. The washer wears out over time and no longer seals.

Repair: Remove the handle, unscrew the packing nut, and pull out the stem. At the bottom of the stem, a rubber washer is held by a brass screw. Replace the washer with an exact-size match. If the valve seat (the brass ring in the faucet body) is pitted, resurface it with an inexpensive seat wrench/grinder tool.

Leaking from the Base

If water pools around the base of the faucet rather than dripping from the spout, the O-rings on the faucet body are worn.

Remove the handle and spout assembly
Locate the O-rings on the faucet body
Cut off the old O-rings and roll on exact replacements
Apply a thin film of plumber’s grease to the new O-rings
Reassemble

Leaking Under the Sink

If water drips from the supply line connections under the sink:

Tighten the compression fittings with tongue-and-groove pliers — a quarter turn is usually enough
If tightening does not stop the leak, turn off the supply, disconnect the line, apply new Teflon tape, and reconnect
Flexible braided supply lines (stainless steel) are more reliable than rigid chrome supply tubes and easier to install

Tips for Success

Take photos during disassembly so you remember the order of parts during reassembly
Bring the old parts to the hardware store to find exact replacements
Use plumber’s grease on O-rings and rubber parts to extend their life and ease assembly
Do not over-tighten. Snug is enough. Over-tightening cracks fittings and deforms seals
If the faucet is more than 15 years old, consider replacing it entirely. A new faucet costs $50 to $200 and eliminates the need for ongoing repairs

When to Replace Instead of Repair

Replace the entire faucet if:

Repair parts are no longer available for the model
The faucet body is corroded or cracked
Multiple components have failed simultaneously
You want to upgrade the style or add a water filtration feature

A faucet replacement is a straightforward project using a basin wrench and standard hand tools. Most replacements take under an hour.