To fix a leaky kitchen faucet, close the hot and cold shutoff valves under the sink, then pinpoint exactly where water is escaping: the spout, the faucet handle, the faucet base, the spray hose, or one of the supply connections. Next, find the faucet’s brand and model so you know which mechanism is inside, and replace the worn cartridge, washers, O-rings, or seals with the exact matching parts.
Location first, mechanism second. That order matters, because buying the wrong part is the most common DIY mistake. A faucet dripping once per second wastes more than 3,000 gallons a year according to EPA WaterSense, and household leaks together can waste close to 10,000 gallons annually and add as much as 10% to a water bill. A small drip is rarely just a small drip. The steps below are a framework; exact disassembly varies by model.
Where Do Kitchen Faucet Leaks Start on a Kitchen Sink?
Constant dripping from the spout points to worn seals that are no longer closing. Water near the faucet handle or the spout base points somewhere else entirely. Guess at the type of valve inside and you will likely come home from the hardware store with a repair kit that does not fit your faucet.
Dry the whole faucet with a towel first, then watch where water reappears.
| Where water appears | Likely cause | What to do next |
| Water drips from the spout tip while the faucet is off | Worn cartridge, flattened washers, corroded valve seat, or failed ceramic seal | Identify the model, then replace the closure component |
| Water under or around the faucet handle | Loose packing nut, worn stem O-ring, damaged cartridge | Remove the handle and inspect the retainer and cartridge seals |
| Water around the rotating spout base | Worn spout body O-rings, or ordinary sink splash | Dry it, wrap a paper towel around the base, then run the faucet |
| Spray head or pull-down hose drips | Loose head connection, cracked hose, worn washers | Replace the hose or spray head part, not the main valve |
| Water under the sink only while running | Pull-down hose, quick-connect fitting, drain joint, or faucet body | Watch each joint with a flashlight while someone runs the faucet |
| Water under the sink even when off | Supply line, braided connector, or the shutoff valves | Close the stops immediately; a pressurized leak is the urgent kind |
What Type of Kitchen Faucet Do You Have?
Most kitchen faucets use one of four kinds of valves, and each has a part that typically fails:
- Compression: two handles that turn several full rotations and tighten as they close. The rubber stem washers usually fail first, followed by the valve seats.
- Cartridge: one or two handles that lift and rotate smoothly to a fixed stop. The faucet cartridge or its O-rings wear out.
- Ball: a single handle with a rounded or dome-shaped cap. Rubber seats, springs, the cam, and packing are the usual culprits.
- Ceramic disc: two ceramic disks inside a cylinder. Inlet seals clog or flatten, or the disc cartridge itself gets scored.
One caution: not every two-handle faucet uses compression valves. Plenty of newer two-handle models use cartridges, so the handle count is not proof. The part you pull out, or the manufacturer’s parts diagram, tells you far more than appearance does.
How to Find the Correct Replacement Parts for Your Faucet Model
Look for the brand on the spout, the faucet handle, or the base ring. If nothing is visible, check for a tag on the supply line under the sink, dig out the original paperwork, or use the manufacturer’s online product-identification tool to match your faucet to a parts diagram.
Cartridges that look nearly identical often differ in length, tab position, stem shape, and hot/cold orientation. Confirm the part number before you take anything apart. Many manufacturers cover cartridges, washers, and seal kits under a long-term or lifetime warranty, so request replacement parts from them before buying generic equivalents.
If the faucet swap is being coordinated with a new sink, countertop, or cabinet layout, a design-build remodeler such as America’s Dream HomeWorks can resolve deck-hole placement, faucet reach, clearances, and plumbing locations as part of one plan.
Tools and Prep: Turn Off the Water Supply First
- Flat-head and Phillips screwdrivers
- Hex or Allen keys for handle set screws
- Adjustable wrench, slip joint pliers, needle nose pliers
- Cartridge puller, if your model needs one
- Flashlight, towels, and a shallow pan
- Silicone plumber’s grease rated for potable water
- White vinegar for mineral deposits
- Your phone, for photographing each layer
- The exact replacement cartridge, washers, O-ring set, or rebuild kit
Gather the basic tools before you start, because a half-open faucet is a bad time to go shopping. Turn off the water at both the hot and cold valves under the sink, then open the faucet to confirm the flow has stopped and to release pressure. Plug the drain so screws, clips, and springs cannot disappear down the pipe. If one of the valves is seized, weeps at the stem, or will not stop the flow, do not force it: shut off the water at the main or call a plumber.
General Steps: How to Fix a Leaky Faucet, Layer by Layer
- Pry off the decorative cap or button on the faucet handle with a small flat-head screwdriver.
- Back out the set screw with an Allen wrench, or remove the top screw if your model uses one.
- Lift the handle straight off. Rocking it hard can bend the stem.
- Loosen the bonnet nut or threaded retaining ring, or pull the clip holding the valve in place.
- Extract the cartridge, stem, or ball assembly, keeping track of how it sat.
- Inspect for flattened washers, torn O-rings, scoring on sealing surfaces, corrosion, cracked plastic, or scale.
- Use white vinegar to clean mineral deposits from the valve body, taking care not to scratch the cartridge bore or valve seat.
- Spread a thin coat of silicone plumber’s grease on new O-rings only if the manual calls for it, then install the replacement in its original orientation.
- Reassemble in reverse order without over-tightening, which can crack a plastic cartridge or distort a seal.
- Reopen the valves slowly and let the faucet run to flush loose debris.
Photograph each layer as you go. Most of how to fix a leaky kitchen faucet is keeping track of what came off in what order, and that one habit saves more reassembly headaches than any tool on the list.
Repair Instructions by Kitchen Faucet Type
Once the valve is out, replacing worn parts takes basic hand skills and minimal effort.
Compression Faucet: Replace the Washers and Check the Valve Seat
Unscrew the stem, remove the brass screw at its base, and swap the rubber seat washer for one of identical size and profile. Then shine a light into the valve seat. A pitted or corroded seat will chew through new washers within weeks and may need dressing with a seat wrench or a full seat replacement.
Leaks at the Faucet Handle: Loose Packing Nut or Worn O Ring
If water escapes at the handle rather than the spout, the closure parts are fine and the problem sits above them. A loose packing nut is the easy case: snug it an eighth of a turn at a time until the weeping stops. If it is already tight, replace the stem packing or the O ring that seals the stem, since that seal hardens and flattens with heat and age.
Cartridge Faucet: Replace a Worn Faucet Cartridge and Its O-Rings
Pull the retaining clip with needle nose pliers and set it somewhere safe. If mineral scale has locked the cartridge in place, use a cartridge puller rather than prying. Note the alignment before it comes out, because installing it rotated will reverse hot and cold. Replacing O rings in the spout body at the same time costs little and prevents a second teardown.
Ball Faucet: Seats, Springs, and Cam Assembly
Remove the dome cap and the cam and packing above the ball. When the spout drips while the faucet is off, the small rubber seats and springs in the valve body are almost always the problem. Use the manufacturer’s rebuild kit, replace the cam, packing, and O-rings together, and check the ball for scoring before reusing it.
Ceramic Disc Faucet: Clean or Replace the Inlet Seals
Lift the cylinder out and look at the inlet seals underneath. Sediment and hard-water scale often hold them open; soak them and the valve body in vinegar. Replace seals that are flattened or cracked, and retire the whole disc cartridge if the ceramic surfaces are chipped. Regular cleaning of the aerator slows the buildup that shortens seal life.
Leaking Under the Sink? Check Supply Connections and Kitchen Cabinets
Empty the cabinet and get a flashlight in there. Have someone run the faucet, cycle hot and cold, and pull the spray hose through its full range of travel while you watch every joint. A leak that only shows up during use usually traces to the pull-down hose, a quick-connect fitting, the spray-head washers, or the faucet body. Check the drain tailpiece and its slip nuts too. If the leak continues with the faucet off, it is on the pressurized side: the supply connections, the braided connector, or the stop valves.
Wrap a dry paper towel around each connection to catch slow seepage. A loose compression or quick-connect fitting can be snugged by hand plus a light turn with a wrench, never forced. Dark staining or swelling on the cabinet floor and flooring means the leak has been running a while and your kitchen cabinets may already be damaged.
How to Test the Repair Before You Call It Done
- Leave the faucet off for 10 to 15 minutes, then check for a dry spout and a dry handle.
- Run hot and cold separately, at low flow and full flow.
- Cycle the spray modes and extend and retract the pull-down hose fully.
- Paper-towel every one of the supply connections one more time.
- Clean the aerator if flow dropped after the repair, since debris loosens during disassembly.
If the faucet is dry but your water use still looks high, EPA suggests reading your water meter, avoiding all water use for two hours, then reading it again. Movement means another leak somewhere.
Repair or Replace a Leaky Faucet? When to Call a Professional Plumber
Repair makes sense when the faucet body is sound, the leak traces cleanly to a cartridge, washers, an O-ring, or a hose, the exact part is still available, and both shutoff valves work. Rebuilding a solid faucet rather than replacing it will save money, and swapping a complete cartridge is often more reliable than chasing one seal at a time.
Replace the entire faucet when the body is cracked or badly corroded, parts are discontinued, several components are failing together, leaks keep returning after correct repairs, the mounting hardware has corroded, or a new sink or countertop makes a new faucet the simpler choice.
Shopping for a new faucet? Federal rules cap kitchen faucets at 2.2 gpm at 60 psi, and California generally limits them to 1.8 gpm with an allowed temporary boost to 2.2. Look for compliance with ASME A112.18.1/CSA B125.1 plus NSF/ANSI/CAN 61 and 372. Kitchen faucets are not eligible for the WaterSense label, so ignore that claim and aim for a model rated 1.5 to 1.8 gpm.
Call a plumber if the valves will not isolate the water, a supply line or stop starts leaking, internal parts seize or break during removal, or the drip continues after a correct cartridge is installed. For Folsom homeowners whose leak has exposed damaged kitchen cabinets or prompted a broader kitchen update, Capital Construction is one local remodeling resource offering a full range of kitchen services, while a stand-alone cartridge, hose, or valve repair stays a plumber’s job.
Frequently Asked Questions About Leaky Kitchen Faucets
Can you fix a leaky faucet yourself? Yes, for most repairs involving washers, O-rings, cartridges, and spray hoses, using basic tools and the correct part. Step back if the valves will not close, a retaining nut is seized, or a part breaks during removal.
What is the most common cause of a leaky faucet? Worn seals: rubber washers, O-rings, and cartridge seals that have hardened or flattened with use. Hard-water scale speeds this up by abrading seals and holding them slightly open.
Why does my kitchen sink leak even when the faucet is off? That is a pressurized leak, which means the supply connections, a stop valve, or a braided connector. Shut off the water at both valves and inspect the fittings right away, because this type causes real damage to cabinets and flooring.
Why is my faucet still dripping after I closed the valves? Often it is residual water draining from the spout, which should stop within a minute or two. If water flows steadily with both valves fully closed, they are not seating and need a plumber.
How do I know if I need washers or a cartridge? A two-handle faucet whose handles turn several rotations and tighten as they close almost always uses washers. A handle that stops at a fixed position uses a cartridge, and the parts diagram for your model confirms it.
