This guide covers fixing a leaky faucet across all four valve types found in residential faucets: compression, cartridge, ball, and ceramic disc. The drip location (spout vs. handle base vs. under the sink) and the handle configuration (two handles that turn vs. a single lever) identify the valve type and the correct repair approach. Each valve type has a different internal mechanism and a different part that wears out first. Using the wrong fix for the valve type wastes time and leaves the drip unresolved.
A faucet dripping once per second wastes approximately 3,000 gallons annually. The parts to fix any of the four types cost between $4 and $30. Total repair time, including shutting off the supply and reassembling, is typically 30–60 minutes for a first-time repair and under 20 minutes for anyone who has done it before. For kitchen-faucet-specific issues including sprayer hose leaks, supply line connections, and escutcheon plate seals, see the companion article How to Fix a Leaky Kitchen Faucet.
Time: 30–60 minutes. Cost: $4–$30. Difficulty: Beginner. Permit required: No. Shut-off valves required: Yes — under the sink or at the main.
Identify Your Faucet Type Before Buying Parts
The four types by handle and behavior:
Compression faucet
Two separate handles, each turns clockwise to close. Feel a slight resistance that increases as you tighten to stop the drip. Common in homes built before 1980. The leak is caused by a worn rubber seat washer or O-ring inside the packing nut. Parts: seat washer ($1–$3) and/or O-ring set. The seat washer is held by a single brass screw at the bottom of the stem. This is the oldest and simplest faucet type to repair.
Cartridge faucet
Either one or two handles, but handles move up-down or left-right rather than rotating to a stop. Drips from the spout even with the handle fully off indicate a worn cartridge. Cartridges are brand-specific and not interchangeable — Moen, Delta, Price Pfister, American Standard, and Kohler each use proprietary cartridge geometry. Parts: replacement cartridge, brand-matched ($8–$25). Note the cartridge orientation before pulling it out — cartridges installed backward drip immediately.
Ball faucet
One handle that moves in a hemisphere — left/right for temperature, up/down for volume. Almost exclusively found in kitchen sinks (this is the classic single-lever kitchen faucet). Drips can come from the spout, the body, or around the base. Caused by worn springs and seats, O-rings on the ball, or a cracked ball itself. Parts: ball faucet repair kit, brand-matched ($12–$20) — buy the kit rather than individual parts, as multiple components typically fail together. Delta Model 100, Moen 7400, Price Pfister Marielle are common examples.
Ceramic disc faucet
One lever over a wide cylindrical body, or two levers on a deck-mount body. The handle pushes a ceramic disc up to open the flow and down to close. Ceramic disc valves rarely drip — when they do, it is usually due to mineral deposits on the disc surfaces rather than worn seals. Parts: ceramic disc cartridge ($15–$30) or cleaning with white vinegar if mineral buildup is the cause. Ceramic disc faucets are the most durable type and are found in higher-end kitchen and bathroom fixtures.
Universal Pre-Repair Steps (All Types)
Step 01 · Shut off the supply valves under the sink
Under every sink are two angle stop shut-off valves — one for hot (left, red-handled or unlabeled on the left side) and one for cold (right, blue-handled or unlabeled on the right side). Turn both clockwise until fully closed. Turn on the faucet to release any pressure remaining in the lines. If the angle stop valves are frozen or croded (they haven't been turned in years), turning them with a wrench can shear the valve body — use caution. If they won't close properly, turn off water at the main supply valve instead. Plug the drain before disassembly — small parts like seat screws and O-rings find the drain immediately.
Step 02 · Document the handle assembly before removing anything
Take a clear photograph of the faucet from above and from the front before touching any part. This photo will save you from the common confusion of reassembly — which handle is hot vs. cold, which direction the cartridge is oriented, where the decorative cap goes. Lay a clean white towel on the counter and set each part on it as you remove it, left to right in removal order, so reassembly is simply the reverse of the photo.
Step 03 · Find the model number
The model number is usually stamped on the body of the faucet where the spout meets the deck, or on a tag attached to the supply lines under the sink. Write it down before leaving for the hardware store — it is the only reliable way to get the correct cartridge or ball kit for your specific faucet. "Moen single-handle" identifies dozens of models; the actual model number narrows it to one replacement cartridge.
Compression Faucet Repair
Step 04 · Disassemble the handle and stem
Pry off the decorative cap on top of the handle with a flathead screwdriver. Remove the screw underneath (Phillips or flat, usually #8 or #10). Lift off the handle. Below the handle, the packing nut is a hexagonal brass nut — unscrew it counterclockwise with an adjustable wrench (protect the finish with tape on the wrench jaws if the nut is visible). The stem lifts straight out. At the bottom of the stem is a rubber seat washer held by a brass screw. Remove the screw, remove the washer, take it to the hardware store for an exact-size match.
Step 05 · Replace the seat washer and O-ring
Press the new washer onto the seat and drive the retaining screw until snug — not overtight, or the screw will strip the soft brass. Inspect the O-ring on the stem body (the thin rubber ring that seals the stem as it moves through the packing nut). Replace it with an exact-diameter match using O-ring lubricant (plumber's grease) to ease installation. Reassemble in reverse order. Turn the supply valves on slowly and test for drip. For most compression faucets, this repair costs under $5 and takes under 30 minutes.
Cartridge Faucet Repair
Step 06 · Remove the cartridge
Remove the handle as in Step 04. The cartridge is retained by a retaining nut, retaining clip, or retaining ring depending on the brand. Moen cartridges use a U-shaped retaining clip at the top of the cartridge body — pull it straight up and out with needle-nose pliers. The cartridge then lifts straight out. Delta cartridges require unscrewing a ball cap and cam. American Standard cartridges use a retaining nut. Consult the brand-specific instruction sheet in the replacement cartridge box — every manufacturer provides one.
Step 07 · Install the replacement cartridge in the correct orientation
Align any orientation tabs or notches on the new cartridge with the corresponding marks on the valve body. For Moen cartridges, the two ears on the cartridge must align with the slots in the valve body, and the cartridge must sit with the hot side facing toward the back of the faucet. Insert the cartridge fully, replace the retaining clip or nut, reassemble the handle. Turn on supply valves. If hot and cold are reversed at the handle, the cartridge was installed 180 degrees out of orientation — remove and reinstall with it rotated.
Ball Faucet Repair (Single-Handle)
Step 08 · Use a repair kit, not individual parts
Ball faucet repair kits (Delta, Moen, or Price Pfister, matched to your model number) contain all the components that typically fail together: two seat springs, two valve seats (rubber cups), O-rings for the body, and sometimes a replacement ball. Remove the handle (set screw under the handle cap, usually Allen/hex key). Unscrew the ball cap counterclockwise. Lift out the cam, packing, and ball. With a flathead screwdriver, pry out the two spring/seat assemblies from the inside of the valve body. Install new seats (convex side down, cupped side up), then new springs on top. Install the new ball (align the pin on the ball with the slot in the valve body). Replace the cam, packing, and cap. Replace the body O-rings if provided in the kit. Reassemble.
Ceramic Disc Faucet Repair
Step 09 · Clean or replace the disc cartridge
Remove the handle. The disc cartridge is a wide ceramic cylinder inside the valve body — unscrew the cartridge housing counterclockwise and lift out the disc cartridge. Inspect the two ceramic disc faces. If mineral deposits are visible (white or tan scale), clean both faces with white vinegar and a soft cloth. Do not use abrasive pads on ceramic disc surfaces — any scratching destroys the seal. Rinse thoroughly with clean water, dry, and reassemble. If the ceramic faces show visible cracks or chips, replace the entire disc cartridge. Turn on the supply valves slowly after ceramic disc work — a sudden pressure surge can crack a new ceramic disc.
Common Mistakes to Avoid
Buying a universal cartridge. Cartridges are brand-specific. A Delta cartridge will not fit a Moen valve body, and vice versa. Always get the model number before buying.
Installing a cartridge backward. A reversed cartridge drips immediately and may have hot and cold reversed at the handles. Photograph orientation before removal.
Overtightening the seat washer screw. The retaining screw threads into soft brass. One turn past snug is enough; stripping it requires extracting a brass insert.
Not plugging the drain. The seat washer retaining screw is 3/16 inch and will fall into the drain instantly. Plug the drain before any disassembly.
Skipping the O-ring inspection on compression stems. A new seat washer on a worn O-ring produces a drip from around the handle base rather than the spout. Replace both at the same time.
Turning supply valves back on at full speed. Open slowly — a pressure surge after disassembly can dislodge seals that are not fully seated.
When to Call a Professional
A plumber is warranted when the shut-off valves under the sink will not close (valve replacement requires turning off water at the main and may involve soldering or compression fitting work); when the faucet body itself is cracked (the faucet must be replaced, not repaired); or when leakage is at the base of the faucet deck where it meets the countertop (indicates a failed escutcheon seal or corroded deck mount, see the kitchen faucet repair guide for deck-mount and escutcheon repair). For bathroom faucet repairs and running toilet issues, see the bathroom repair index.
Follow-Up Maintenance
Inspect faucet aerators annually — unscrew the aerator from the spout tip and clean mineral deposits with white vinegar. A clogged aerator reduces flow and increases pressure upstream of the valve, accelerating seal wear. Replace cartridges proactively every 5–8 years in homes with hard water. Compression faucet seat washers last 3–5 years in typical use. If a faucet required multiple repairs within two years, the valve body may be corroded — faucet replacement rather than further repair is the more cost-effective path at that point.
Related Kitchen and Repair Guides
How to Fix a Leaky Kitchen Faucet — kitchen-specific guide covering sprayer hose, supply lines, escutcheon plate, and pull-down faucets
Filed by HowTo: Home Edition. This is a Repair × Kitchen guide covering leaky faucet repair across all four valve types. The four-type framework — compression, cartridge, ball, ceramic disc — is the correct diagnostic entry point for any dripping faucet before any parts are purchased. Each type has one or two components that wear first; knowing the type reduces the repair to a parts swap rather than a guessing exercise.
Common Questions About Faucet Leak Repair
How do I identify my faucet type if I'm not sure? The most reliable indicator is handle behavior: does the handle rotate clockwise to stop the water (compression)? Does it move up-down or side-to-side without a defined stop (cartridge)? Does it move in a hemisphere — left-right for hot-cold and up-down for volume (ball faucet)? Does it pivot over a wide cylindrical body (ceramic disc)? If still unclear, note the brand (visible on the faucet body) and search the brand's website for the model number — most brands provide cross-reference guides from model number to internal valve type.
How do I find the faucet model number? The model number is stamped or embossed on the faucet body, typically at the base of the spout where it meets the deck, or on the underside of the spout. It may also be on a paper tag attached to the supply lines under the sink. The model number was also printed on the original installation manual — if the home is newly purchased and the previous owner left documentation in a kitchen drawer, check there first. Hardware stores and plumbing suppliers can look up cartridges by brand name and a description if the model number is not findable — they maintain large cross-reference books for this purpose.
Can I just tighten the packing nut to stop a compression faucet from dripping? Tightening the packing nut stops a leak around the handle stem but does not fix a drip from the spout. The spout drip in a compression faucet is caused by the seat washer at the bottom of the stem failing to fully close against the valve seat. Tightening the packing nut applies more friction to the stem as it rotates but does not change the sealing surface at the bottom. Replace the seat washer.
My cartridge faucet drips even with the handle in the closed position after I replaced the cartridge. What did I do wrong? The most common cause is an incorrectly oriented cartridge. Moen cartridges in particular must be installed with the cartridge stem at a specific rotational position — the flat or key on the cartridge must align with the flat in the valve body. If the cartridge is 180 degrees out of position, the "off" position of the handle corresponds to a partially open valve position in the cartridge. Remove the cartridge, rotate it 180 degrees, reinstall, and test. If the drip stops, the original orientation was incorrect.
Is it worth repairing an old faucet or should I replace it? Repair is generally more cost-effective than replacement for faucets under 15 years old with a sound body. The valve seats (the surfaces the cartridge or seat washer seals against) are the limiting factor — if the seat surface is deeply grooved or pitted, replacement parts will not seal reliably and the faucet will require repeated repairs. For faucets with badly damaged valve seats and good-quality bodies (Moen, Delta, Kohler), a valve seat grinder can resurface the seat for $20–$40, extending the faucet life. For faucets with corroded or cracked bodies, or for faucets under $30 in current replacement value, replacement is more cost-effective than continued repair.
Ceramic disc cartridge (Kohler, Grohe): $20–$35 for most popular models.
Professional plumber repair: $100–$200 service call for a dripping faucet. DIY saves $80–$190 for a repair that takes under one hour with the correct cartridge in hand.
Annual water waste at 1 drip/second: approximately 3,000 gallons = $18 at national average water rates. The repair pays for itself in 2–6 months.
Brand-Specific Cartridge Reference
Faucet cartridges are not interchangeable between brands or models. This reference covers the most common residential brands and their standard cartridge identifiers.
Moen. The most widely used cartridge system in North America. The standard single-handle cartridge is the 1225 (standard) or 1225B (replacement with brass body). Moen offers cartridge replacement at no charge through their lifetime warranty program — call 1-800-BUY-MOEN or visit their website with the model number. Moen cartridges are identified by the U-shaped brass retaining clip at the top of the cartridge body.
Delta. Delta single-handle faucets use a ball-type mechanism rather than a cartridge. The ball is a hollow sphere with a stem and three ports. The standard repair kit for Delta single-handle is the RP3614 (seats and springs) or RP70 (complete ball kit). Delta two-handle faucets use a ceramic cartridge secured by a retaining nut.
Kohler. Kohler single-handle faucets use a ceramic disc valve cartridge, typically the GP1084167 for widespread models or the GP30413 for single-hole models. Kohler cartridges are secured by a retaining nut that unthreads counterclockwise. The cartridge is extracted with a Kohler-specific cartridge puller (GP72010) or by gripping the stem with pliers and pulling straight up with firm even force.
Price Pfister / Pfister. Uses a variety of cartridge types by product line. The Pfister 910-031 is a common single-handle cartridge. Pfister customer service provides free replacement cartridges under their "Pforever Warranty" — contact them directly before purchasing at retail.
American Standard. Two common cartridge systems: the Aquaseal ceramic cartridge (used in widespread two-handle faucets) and the Monoblock cartridge for single-handle models. American Standard cartridges use a retaining nut and seat with a slightly larger hex than standard cartridges — verify the wrench size before disassembly.
Grohe / Hans Grohe. German-engineered ceramic disc cartridges, typically identified by diameter (46mm, 35mm). These are among the most durable cartridges in residential plumbing — Grohe cartridges frequently outlast the faucet body. When they do fail, the replacement is brand-specific and available through plumbing supply houses rather than standard hardware stores.
When in doubt about cartridge compatibility: bring the removed cartridge to a plumbing supply house rather than a general hardware store. Plumbing supply professionals maintain cross-reference catalogs and can match cartridges that hardware store staff cannot identify.
Time: 30–60 minCost: $4–$30Difficulty: BeginnerBy: HowTo: Home Edition
Four faucet types, four distinct repair paths. Identify the valve type before buying a single part — the wrong cartridge or seal will not fix the drip. This guide covers compression, cartridge, ball, and ceramic disc valves. For kitchen-specific issues (sprayer hose, supply lines, escutcheon plate), see How to Fix a Leaky Kitchen Faucet.
Plug the drain before disassembly. The retaining screw for a seat washer is 3/16 inch and drops directly into an open drain. This is not a hypothetical.
Identify Your Faucet Type
Compression
Two handles that rotate to a definite stop
Replace the rubber seat washer (held by a brass screw at the bottom of the stem) and the O-ring on the stem. Parts: $1–$5.
Cartridge
One or two handles that move up-down or side-to-side, no rotational stop
Replace the cartridge — brand-specific, not interchangeable. Get the model number before buying. Parts: $8–$25.
Ball
Single lever that moves in a hemisphere (left-right for temp, up-down for volume)
Use a brand-matched ball repair kit — contains springs, seat cups, O-rings, and ball. Parts: $12–$20.
Ceramic Disc
Single lever over a wide cylindrical body
Clean mineral deposits with white vinegar, or replace the disc cartridge. Parts: $0 (cleaning) or $15–$30 (replacement).
Before Opening Any Faucet
Step 01
Shut off supply valves, photograph the assembly
Turn both angle stop valves under the sink fully clockwise. Open the faucet to release line pressure. Plug the drain. Photograph the handle assembly from above and front before removing anything. Find the model number stamped on the faucet body or on the supply line tag.
Compression Faucet
Step 02
Replace the seat washer and O-ring
Pry off the handle cap, remove the handle screw, lift the handle. Unscrew the packing nut counterclockwise. Lift out the stem. At the stem bottom: one brass screw holds the rubber seat washer. Replace the washer with an exact-diameter match and replace the O-ring on the stem body with plumber's grease applied. Reassemble in reverse.
Cartridge Faucet
Step 03
Remove and replace the cartridge
Remove the handle. Extract the retaining clip or nut (Moen uses a U-clip pulled straight up with needle-nose pliers). Lift out the cartridge. Note its orientation — a photo before removal is essential. Install the replacement cartridge in the same orientation. If hot and cold are reversed after reassembly, the cartridge is 180° out — remove and rotate it.
Ball Faucet
Step 04
Use a full repair kit
Remove the handle set screw (Allen key), lift off the handle, unscrew the ball cap. Lift out cam, packing, and ball. Pry out the spring/seat assemblies with a flathead screwdriver. Install new seats and springs from the kit (convex side down, springs on top). Install the replacement ball, aligning the pin with the slot in the body. Reassemble with the new O-rings and cam packing provided in the kit.
Ceramic Disc Faucet
Step 05
Clean mineral deposits or replace the disc cartridge
Remove the handle and unscrew the cartridge housing. Clean ceramic disc faces with white vinegar and a soft cloth — no abrasives. If faces show cracks or chips, replace the cartridge. Open supply valves slowly after ceramic disc work — a pressure surge can crack new ceramic.
Common Mistakes
Buying a universal cartridge — cartridges are brand-specific
Installing a cartridge backward — drip resumes and hot/cold may be reversed
Skipping the O-ring on a compression stem — leak moves to the handle base instead of the spout
Not plugging the drain — small parts fall in immediately
