A dripping faucet is one of the most common household annoyances, and it is also one of the most wasteful. A single drip per second adds up to roughly 3,000 gallons of wasted water per year, enough to fill close to 40 standard bathtubs. Beyond the water bill, chronic leaks stain sink surfaces, corrode drains, and tax the plumbing lines that carry the water. Most leaks trace back to one of two internal parts, a worn cartridge or a worn stem washer, and replacing those parts is a repair most homeowners finish with a few basic tools. The diagnosis matters as much as the fix, and the leaky faucet repairs guide walks through identifying the problem before you open the faucet.
Why Faucets Leak
Every faucet controls water with a valve that opens and closes thousands of times a year. Cartridge faucets use a sealed cartridge that slides or rotates to regulate flow. Compression faucets use a threaded stem that presses a rubber washer against a metal seat. Both designs wear out, but they fail in predictable ways. Knowing the internal layout of your faucet, which varies with mounting style and connection type across kitchen and bathroom models, helps you order the right part the first time. The range of faucet types, mounting options, and connections is covered in the faucet installation guide.
Cartridge Faucets: The Modern Standard
Single-handle and many two-handle faucets use cartridges. A cartridge is a self-contained unit that holds the seals and moving parts. When it wears, water bypasses the seals and drips from the spout. Replacing the cartridge restores the faucet to like-new condition, and the part usually costs between $5 and $30.
Compression Faucets: The Old Reliable
Compression faucets have been around for more than a century and remain common in older homes and utility sinks. A rubber washer on the end of the stem seals against a metal seat inside the body. The washer flattens over time, the seal breaks, and the drip begins. The fix is a new washer, sometimes paired with a new seat.
A third failure point sits at the base of the faucet. O-rings around the valve body keep water from leaking where the faucet meets the sink, and when they dry out or crack, water pools around the base and drips into the cabinet. The fix is a simple O-ring kit, and it is often the repair people miss when they only look at the spout.
| Symptom | Likely cause | Typical repair |
|---|---|---|
| Drip from the spout, single handle | Worn cartridge | Replace the cartridge |
| Drip from the spout, two handles | Worn stem washer | Replace washer and seat |
| Water pooling around the base | Failed O-rings | Replace the O-ring set |
| Handle stiff or leaking at the stem | Worn packing | Replace packing or O-ring |
Shutting Off the Water Before You Start
Every faucet repair starts with cutting the water supply. Locate the shutoff valves under the sink, one for hot and one for cold, and turn both clockwise until they stop. If the sink has no individual shutoffs, close the main water valve for the house. Independent DIY repair guides agree on this first step, because opening a faucet under pressure turns a twenty-minute job into a flooded cabinet.
- Clear the cabinet under the sink so you can reach the valves.
- Turn both shutoff valves clockwise to the closed position.
- Open the faucet handle fully to drain the remaining water from the lines.
- Set a towel and a small bucket under the valve area to catch drips.
- Confirm the water is off by opening the faucet; no flow means you are ready.
What to Do When Shutoff Valves Are Stuck
Old shutoff valves sometimes refuse to turn. Apply penetrating oil and wait a few minutes before trying again. Never force a valve with pliers, because a broken valve body means replacing the valve or the supply line. If the valves are corroded beyond use, close the main house valve, do the repair, and schedule a valve replacement for another day.
Gather the tools before you start: an adjustable wrench, a basin wrench for tight spaces, pliers, a screwdriver, plumber tape, and a small container for screws. A flashlight helps you see into the valve body, and needle-nose pliers make cartridge removal easier when the part is stuck.
Identifying Your Faucet Type Before Buying Parts
Look under the handle or at the manufacturer marking to determine whether you need a cartridge or a washer kit. Cartridge faucets typically hold a plastic or brass cartridge with a retaining clip. Compression faucets expose a threaded stem with a hex nut. Taking the old part to a hardware store guarantees a match.
Repairing a Cartridge Faucet
Cartridge replacement is the most common faucet repair. The cartridge sits inside the valve body, and most designs follow the same removal sequence. Many newer faucets, including sensor-activated models, rely on the same quarter-turn ceramic cartridge found in manual designs, which is why the procedure translates across product categories. The workings of touch-free models are explained in the sensor-activated faucet technology guide.
- Remove the handle screw, which may hide under a decorative cap.
- Lift the handle off the stem.
- Unscrew the retaining nut or pull the retaining clip.
- Pull the cartridge straight out, using pliers if it sticks.
- Install the new cartridge in the same orientation and reassemble.
- Turn the water back on and test for drips.
Single-Handle vs. Two-Handle Cartridge Faucets
Single-handle faucets use one cartridge that blends hot and cold water. Two-handle cartridge faucets use a separate cartridge per side. The repair steps are identical in principle, but order the cartridge for the correct side, because left and right cartridges are sometimes mirror images.
Repairing a Compression Faucet
Compression faucets fail when the washer wears or the seat develops a groove. Both parts are inexpensive, and the repair takes about thirty minutes. If the faucet body itself is corroded or the threads are stripped, replacement is the better route; the installation steps for a new bathroom sink and faucet describe swapping the entire unit.
- Remove the handle and the packing nut with an adjustable wrench.
- Lift the stem assembly out of the faucet body.
- Unscrew the brass screw that holds the washer to the stem.
- Install a new washer of the same size and shape.
- Inspect the seat; if it is rough, remove it with a seat wrench and install a new one.
- Reassemble the stem, packing nut, and handle, then test for drips.
Seats, Springs, and the Hardware That Makes the Seal
A washer only seals when the seat beneath it is smooth. A scored seat shreds a new washer within weeks. Seat wrenches reach into the valve body to remove the seat for replacement, and some faucets include a spring that holds the washer against the seat, so a missing or weak spring produces the same drip as a worn washer.
Reseating a Damaged Valve Seat
If the seat is removable, replace it outright. If it is fixed to the body, a seat-dressing tool grinds the surface smooth again. Both options cost less than a new faucet and restore the seal.
Reassembly order matters. The packing nut must seat evenly, or the handle binds and the stem leaks around the top. Tighten it snugly, then back off a quarter turn so the handle moves freely. Overtightening the packing nut is the most common cause of a handle that refuses to turn after a repair.
When to Replace the Faucet Instead of Repairing It
Some leaks signal the end of the faucet useful life. Hairline cracks in the body, stripped threads, and mineral-caked internal passages all argue for replacement. The comparison below shows why repair usually wins for minor leaks and why replacement takes over once the body itself is compromised. Homeowners planning a broader refresh often combine a new fixture with a sink upgrade, and the bath upgrade project that installs a new sink and faucet shows how the two jobs fit together.
A faucet that has been repaired twice in the past few years is usually cheaper to replace than to keep patching, because every repair cycle adds new wear to the valve body and the finish. The same logic applies when replacement parts for an older model have become hard to find, which happens more often than most owners expect.
| Option | Parts cost | Labor | Typical result |
|---|---|---|---|
| Cartridge replacement | $5–$30 | DIY | Like-new function |
| Washer and seat kit | $3–$10 | DIY | Drip stops |
| New faucet, DIY install | $50–$250 | 1–2 hours | New fixture and warranty |
| New faucet, plumber install | $50–$350 | About 1 hour | Guaranteed install |
Signs That Replacement Is the Smarter Move
- Cracks or corrosion on the faucet body
- Drips that continue after cartridge and washer replacement
- Mineral buildup that clogs the aerator every few weeks
- A finish that is pitted beyond cleaning
Most dripping faucets come back to life with a part that costs less than a pizza. The repair is safe, cheap, and repeatable once you know whether you own a cartridge or a compression design. Owners who decide replacement is the better path can work through the complete faucet guide for homeowners, which covers selecting the right fixture, measuring for fit, and connecting supply lines without leaks. Whether you repair or replace, the goal is the same: a faucet that closes completely and stops giving water away one drop at a time.