How to Replace a Faucet Cartridge: Step-by-Step for Moen, Delta and Other Faucets

Knowing how to replace a faucet cartridge solves a faucet that drips or sticks or runs hot when you want cold. In most cases the cartridge is the part asking for help. The cartridge is the part inside the faucet that controls water flow and temperature. It is small and cheap and you can replace it in about an hour with basic tools.

This guide shows you how to replace a faucet cartridge from start to finish. You will learn how to tell if the cartridge is the problem and how to find the right replacement. You will also see what changes between Moen and Delta and Kohler faucets and what to do when the new cartridge does not fix the leak.

Is the Cartridge Really the Problem?

Check the symptoms before you buy parts.

• A drip from the spout when the faucet is off. This is the classic sign of a worn cartridge or seals.
• A handle that is stiff or loose or does not move through its full range.
• Water that will not get hot or cold or changes temperature on its own.
• Low flow from one side or from the whole faucet.
• A leak around the base of the handle.

Some of these have other causes. Low flow can come from a clogged aerator. A leak at the base of the spout can be a worn O-ring. The EPA explains why even a small drip is worth fixing on its WaterSense Fix a Leak Week page. If the faucet is old and corroded a full replacement may cost less than repairs. Our plumbing repair cost guide shows what a plumber charges so you can compare.

Which Type of Faucet Do You Have?

The steps depend on the faucet design. Look at the handles.

• One handle that moves up and down and side to side. This is a single-handle faucet. It uses one cartridge that controls both flow and temperature. Moen and Delta and Kohler all make these.
• Two handles. These may use a compression valve with a rubber washer or a ceramic disc cartridge. If the handles turn a quarter turn only they likely use ceramic cartridges. If they turn several times they may be compression valves.

This guide shows how to replace a faucet cartridge in a single-handle faucet. If you have a two-handle compression faucet the idea is the same but you replace washers and seats and not a cartridge.

Tools and Parts You Need to Replace a Faucet Cartridge

• Replacement cartridge for your exact model
• Allen wrench set or small screwdriver
• Adjustable pliers
• Cartridge puller if your brand needs one
• Basin wrench for hard to reach nuts under the sink
• Plumber’s grease
• Rag or towel and a small bowl
• Plug or rag for the drain
• White vinegar and an old toothbrush for cleaning mineral buildup

A basin wrench is a long-handled tool made for tight spaces under a sink. You may not need it for a cartridge job but it helps if you also have to disconnect lines.

How to Find the Right Part Before You Replace a Faucet Cartridge

An exact match matters. A cartridge that is close but not identical will leak or not fit.

1. Look for the brand name on the faucet and the model number. It may be on the underside or inside the cabinet.
2. Take off the old cartridge first and bring it to the store. Compare the length and the splines and the ears.
3. Search the part number printed on the old cartridge if there is one.
4. Check the manufacturer’s website. Many have parts diagrams by model.
5. Buy from a source that accepts returns in case it is wrong.

Common cartridges often cost from about $10 to $50 depending on the brand. Specialty and designer faucets may cost more.

How to Replace a Faucet Cartridge Step by Step in a Single-Handle Faucet

Step 1: Turn Off the Water

Look under the sink for the two shutoff valves. Turn them clockwise until they stop. Open the faucet to release pressure and drain the lines. If you do not have shutoff valves turn off the main water supply to the house.

Step 2: Protect the Sink and the Drain

Put a rag in the drain so a small screw cannot fall in. Lay a towel in the sink basin to protect the finish from dropped tools.

Step 3: Remove the Handle

Look for a small cap or a decorative button on the handle. Pry it off with a thin screwdriver. Under it you will find a screw. Some handles use a set screw on the side that needs an Allen wrench. Loosen the screw and lift the handle off. If the handle is stuck wiggle it gently. Do not force it.

Step 4: Remove the Cap or Trim

Some faucets have a dome-shaped cap or a trim ring over the cartridge. Unscrew it by hand or with pliers. Wrap the pliers in a rag so you do not scratch the finish.

Step 5: Remove the Retaining Nut or Clip

The cartridge is held in with a nut or a clip. A threaded nut unscrews with pliers or a wrench. A metal clip pulls out with pliers. Keep any small parts in a bowl so you do not lose them.

Step 6: Note the Position

Before you pull the cartridge out note which way it faces. Many have a notch or a mark that lines up with the hot side. Take a photo with your phone. Putting a cartridge in backward gives you hot water when you want cold.

Step 7: Pull Out the Old Cartridge

Grip the stem and pull straight up. If it sticks twist it gently while you pull. Some brands need a cartridge puller since mineral buildup holds the part in place. Do not pry with a screwdriver since that can damage the faucet body.

Step 8: Clean the Faucet Body

Look inside the faucet body for mineral buildup and debris. Wipe it with a rag. Use vinegar on a toothbrush for stubborn deposits. Remove any old O-rings or seals that stayed behind.

Step 9: Install the New Cartridge

Rub a thin coat of plumber’s grease on the new O-rings. Line up the notch with the hot side marker and push the cartridge straight down until it sits fully. It should seat evenly.

Step 10: Reassemble

Put the retaining nut or clip back and snug it up without overtightening. Put the cap and the handle and the screw back in order.

Step 11: Test

Turn the shutoff valves on slowly. Open the faucet to let air out. Check for leaks at the base and at the handle. Test both hot and cold. If the temperature is reversed remove the cartridge and rotate it 180 degrees.

What Changes by Brand

Brands share the same general process but small details differ. Always check the manual for your model.

Moen

Many Moen single-handle faucets use a cartridge held by a metal retaining clip. The cartridge often needs a puller tool to come out. The cartridge has ears that must line up with slots in the housing. Moen offers a line of cartridges that fit many models so check the part number.

Delta

Delta faucets vary by series. Many single-handle models use a cartridge held under a cap and a nut. Some use a ball and seals and springs instead of a cartridge. Take photos as you go since the parts can be small.

Kohler and Other Brands

Kohler and Price Pfister and Glacier Bay and others use their own cartridges. Look up the model number and buy the matching part. Cheap faucets often cost less to replace than to repair.

What If the Faucet Still Leaks After a New Cartridge?

Work through these common causes.

• The cartridge is not fully seated. Remove it and set it again.
• The O-rings are damaged or dry. Replace and grease them.
• The seats or springs are worn. This happens in ball-type faucets.
• The faucet body has corrosion or a crack. A full faucet replacement may be the better fix.
• A leak that is not at the handle. Check the supply lines and the base of the faucet.
• The water pressure is very high. A pressure regulator can help.

If none of these solve it call a plumber. Do not leave a leak since it can damage the cabinet.

When to Replace the Faucet Instead

Replace the whole faucet if:

• The finish is corroded or flaking
• The body is cracked
• The parts for your model are no longer available
• You have replaced the cartridge more than once
• The faucet is very old

A new faucet may cost less than you expect and updates the look of the bathroom. If you plan a bigger project read our bathroom remodel cost guide.

Replacing a Shower Cartridge

The same idea applies to a shower valve but the steps are different since the cartridge sits in the wall. See our full guide on how to replace a shower cartridge and the one on how to fix a leaking shower head.

Tips to Make It Easier to Replace a Faucet Cartridge

• Take photos at each step
• Lay out parts in the order you remove them
• Keep a towel under your tools
• Do not force stuck parts and use a puller instead
• Clean the faucet body before you install the new part
• Buy a spare O-ring set
• Run the faucet for a minute after the job to flush debris

If you enjoy small repairs our DIY home improvement guide lists the projects that suit beginners and the ones you should leave to a professional.

What Does It Cost to Replace a Faucet Cartridge?

The part is the small cost. Most common cartridges run from about $10 to $50 and you may already own the tools. If you hire a plumber the bill is mostly labor. Our plumbing repair cost guide puts standard residential repairs at roughly $150 to $500 per visit. That makes this one of the repairs where doing it yourself saves real money.

Budget extra time if the faucet is old. Corroded parts take longer to loosen and a seized cartridge may need a puller. If the faucet body is damaged a new faucet may cost less than a repair that keeps failing.

Common Mistakes When You Replace a Faucet Cartridge

Most failed repairs come from a few small errors. Avoid these when you replace a faucet cartridge and the job goes smoothly the first time.

• Skipping the shutoff valves and trying to work with water pressure on
• Buying a cartridge by guess and not matching the old part
• Prying with a screwdriver and scratching the faucet body
• Forgetting to note the hot side before pulling the old part
• Overtightening the retaining nut and cracking the housing
• Reusing dry or flattened O-rings
• Leaving mineral deposits in the faucet body

If you slow down and take photos at each step you will rarely make any of these mistakes. The next time you need to replace a faucet cartridge you will also know exactly how the parts come apart.

Frequently Asked Questions

How do I know if my faucet cartridge is bad?

Common signs are a drip from the spout and a stiff handle and water that will not mix correctly. If the faucet leaks around the handle the cartridge or its seals may be worn.

How much does a faucet cartridge cost?

Many common cartridges cost from about $10 to $50. Designer brands may cost more. A plumber will charge for labor on top of the part.

How long does it take to replace a faucet cartridge?

Most people finish in 30 minutes to an hour. Stuck parts and hard water deposits can add time.

Do I need a special tool to remove a faucet cartridge?

Often pliers and an Allen wrench are enough. Some Moen cartridges need a puller tool.

Can I replace a faucet cartridge without turning off the water?

No. Always shut off the water first. Use the valves under the sink or the main shutoff.

Why is my faucet cartridge hard to remove?

Mineral buildup can lock it in place. Soak the area in vinegar and use a puller tool and twist gently as you pull.

What if I install the cartridge backward?

You will get hot water on the cold side. Shut off the water and rotate the cartridge 180 degrees.

Final Thoughts on How to Replace a Faucet Cartridge

Learning how to replace a faucet cartridge is one of the best small repairs to learn. It costs little and takes less than an hour and fixes drips and sticky handles in most faucets.

Match the part exactly and take photos as you go. Clean the faucet body and grease the seals before you put everything back. If the faucet is old or damaged replace it. Either way you save money and avoid the waste of a dripping tap.

Working under the kitchen sink anyway? See why a garbage disposal hums.