How to Replace a Kitchen Sink Faucet: A Step-by-Step Guide (2026)

To replace a kitchen sink faucet, you will shut off the water supply, disconnect the old supply lines, remove the mounting hardware, set the new faucet in place, connect the lines and check for leaks. Most homeowners can finish the job in one to three hours with basic hand tools, provided the sink holes and shutoff valves are in reasonable condition. This guide covers how to plan the swap, what tools to gather, each installation step, and the mistakes that cause leaks or stripped fittings.

Before You Start: Check Compatibility and Gather Tools

Before you buy or remove anything, confirm that the new faucet will fit your sink. Count the number of holes in the sink deck and measure the center-to-center spacing between them if you have more than one. Standard options include single-hole, three-hole (widespread or centerset), and deck-mounted units with a separate sprayer. Some faucets come with a deck plate that covers gaps, which helps if your old faucet used a different hole pattern.

Check the existing shutoff valves under the sink as well. If they are corroded, stiff or leaking when you turn them, plan to replace them at the same time. Many installers recommend replacing supply lines during a faucet swap, since the old braided lines may be brittle.

Tools and supplies checklist

• Adjustable wrench and basin wrench (a basin wrench reaches the mounting nuts in tight cabinets)
• Bucket and towels to catch residual water
• Flashlight or headlamp
• Plumber’s putty or a silicone sealant rated for sinks, if the new faucet calls for it
• Replacement supply lines, usually 3/8-inch compression to 1/2-inch IPS or similar
• Pliers and a small screwdriver
• Penetrating lubricant for rusty nuts
• Painter’s tape to protect the sink finish

Step-by-Step: How to Replace the Kitchen Sink Faucet

Step 1: Shut off the water supply

Turn the hot and cold shutoff valves clockwise under the sink until they stop. If either valve does not close fully or drips when you turn it, close the main house water supply instead. Then open the faucet to relieve pressure and let the remaining water drain. Place your bucket beneath the cabinet.

Step 2: Disconnect the supply lines and drain

Place the bucket under the connections and use the wrench to loosen the nuts on the supply lines. Hold the valve steady with your other hand so you do not twist the pipe. Disconnect the drain assembly as needed, including the pop-up rod, if your faucet sits near it. Keep small parts together in a labeled bag.

Step 3: Remove the old faucet

Under the sink, you will find mounting nuts or a mounting bracket holding the faucet base to the sink deck. Use the basin wrench to loosen these fasteners. Some faucets have a plastic retaining nut; turn it counterclockwise until it comes off. Once the nuts are removed, lift the faucet straight up. If the old unit is stuck from old sealant, run a plastic putty knife around the base to break the seal. Scrape away old plumber’s putty or caulk from the sink surface so the new faucet seats flat.

Step 4: Prepare the sink surface

Clean the mounting area thoroughly with a non-abrasive cleaner. Check that the holes are clear and that the sink deck is not cracked. If you are installing a faucet with a deck plate, set it in place before the faucet, following the manufacturer’s instructions.

Step 5: Install the new faucet

Thread the supply lines through the holes and feed the faucet body onto the deck. If the manufacturer calls for a bead of silicone or a gasket, apply it now. Tighten the mounting nuts from underneath, working evenly so the faucet sits level. Hand-tighten first, then add a quarter turn with the wrench. Overtightening can crack the sink or damage the base.

Step 6: Connect the supply lines

Attach the hot line to the hot valve and the cold line to the cold valve. Hand-tighten each nut, then snug it with the wrench. Wrap threads with plumber’s tape only if the fitting type calls for it, since compression fittings usually seal with a ferrule and do not need tape.

Step 7: Turn on the water and test

Slowly reopen the shutoff valves, then run the faucet on hot and cold for about a minute each. Watch the connections for drips. Check the sprayer, if your faucet has one, and confirm that the handle moves smoothly through its full range. Let water run until the lines clear of air and sediment.

Common Mistakes to Avoid

• Skipping the shutoff test. If a valve leaks when closed, you will have water coming out of the cabinet during the swap.
• Mixing up hot and cold lines. Hot is usually on the left and cold on the right, but confirm with the faucet’s labels.
• Overtightening compression nuts, which can crack the fitting or the sink.
• Reusing old, stiff supply lines that may fail under pressure months later.
• Forgetting to flush the new faucet’s aerator before judging leaks or flow.

Tips for a Cleaner Installation

Take a photo of the existing setup before you disconnect anything. Use painter’s tape to mark the sink where the new faucet will sit so you can line it up without guessing. Check the faucet’s installation manual for the recommended torque or hand-tight specification, and follow it. If your cabinet is tight, remove the drawer or the items stored under the sink so you have room to work with the basin wrench.

Recommended gear

• Basin wrench: reaches the mounting nuts in tight spaces where a regular wrench cannot fit. View on Amazon
• Braided stainless steel supply lines: more durable than rubber lines and commonly recommended as replacements during a faucet swap. View on Amazon
• Plumber’s putty: seals the base of many faucets and deck plates against the sink surface. View on Amazon
• Penetrating lubricant: helps loosen rusty or seized nuts without forcing them. View on Amazon

If you are also weighing a different style or finish for the new unit, you may find it helpful to compare options before you buy. Our guide to Delta Tap Kitchen Faucet Review: Key Features Explained walks through the features that matter in a kitchen faucet, and Delta Touchless Kitchen Faucet Review (2026) covers a hands-free option if you want to reduce contact with the handle.

FAQ

Do I need a plumber to replace a kitchen sink faucet?

Many homeowners handle this job themselves, since it mainly involves disconnecting and reconnecting supply lines. If the shutoff valves fail, the sink is damaged, or your plumbing has unusual configurations, consult a licensed plumber.

How long does the replacement take?

Plan on one to three hours for a typical installation. Extra time may be needed if the old faucet is seized, the valves are corroded, or you are installing a faucet with a separate sprayer or deck plate.

Should I replace the supply lines when I replace the faucet?

Often yes. Old supply lines can be brittle or corroded, and replacing them during the swap is inexpensive insurance against a future leak. Check the lines for cracks or bulging before you decide.

What is the difference between a one-hole and three-hole faucet?

A one-hole faucet mounts through a single opening, often with the handle and spout combined. A three-hole faucet uses two handles and a spout across three openings. Your sink’s existing holes determine which type will fit without modification.

Do I need plumber’s putty or silicone?

It depends on the faucet and manufacturer instructions. Some faucets call for a gasket, others for putty or silicone sealant under the base. Follow the instructions included with your new faucet.

Why is my new faucet dripping after installation?

Check that the mounting nuts are snug and that the supply line connections are tight. A cartridge or washer that was not fully seated may also cause leaks. Recheck each connection after the water has been running for a few minutes.

Can I replace a faucet without shutting off the main water supply?

Yes, if the individual shutoff valves under the sink close fully and do not leak. If they fail, shut off the main supply to your home before you begin.

Conclusion

Replacing a kitchen sink faucet is a manageable project when you plan ahead, confirm compatibility, and work methodically. Shut off the water first, take the old unit apart carefully, and seat the new faucet evenly before connecting the lines. Test every connection before you call the job finished.

Related reading

• Replace Bathroom Tub Faucet: A Step-by-Step Guide for Beginners
• Moen Bathroom Faucet Parts: Identify, Order and Replace Them Yourself

About the author