How to Replace a Kitchen Faucet (Step-by-Step Guide)
Replace a kitchen faucet yourself and save $150-200 in labor. This guide covers measuring for the right fit, loosening seized nuts with a basin wrench, and testing for leaks.
Quick answer: To replace a kitchen faucet, shut off both under-sink supply valves, disconnect the flexible supply lines from below, use a basin wrench to reach the mounting nut behind the sink deck, and lift out the old faucet. Clean off any old putty or silicone from the deck, set the new faucet, tighten the mounting nut from below, reconnect supply lines with plumber’s tape on the threads, and turn the water back on slowly while watching for drips. The whole job runs 60-90 minutes if the nuts cooperate.
Replacing a kitchen faucet is one of those jobs that costs $150-200 in labor when a plumber does it and about an hour of your time when you do it yourself. The new faucet runs you $90-300 depending on finish and features. The tools are basic, the process is straightforward, and the only real variable is whether the old mounting hardware is seized from mineral deposits.
If your current faucet just drips from the spout rather than needing full replacement, the leaky faucet repair guide may get you there for $10 instead of $90. But if the body is corroded, the handle is loose, or you just want an upgrade, a swap is the right call.
What You’ll Need
Tools:
- Basin wrench (essential for reaching nuts behind the sink deck)
- Adjustable wrench or channel-lock pliers
- Plumber’s tape (Teflon tape)
- Utility knife or putty knife
- Flashlight or headlamp
- Bucket and old towels
Materials:
- New kitchen faucet (check the hole count and spacing before buying)
- New flexible supply lines if the existing ones are more than 10 years old
- Plumber’s putty or silicone caulk (check your new faucet’s instructions, most modern faucets include a gasket and don’t need putty)
Cost estimate: Budget $90-150 for a basic single-handle pull-out; $180-300 for a mid-range pull-down with a spray head. Spend on the faucet, not on supply lines, $15 braided stainless lines from the hardware store are fine.
Step 1: Measure Before You Buy
Pull open the cabinet under your kitchen sink and count the holes in the sink deck. Single-hole faucets need one hole. Centerset faucets use three holes spaced 4 inches apart (center to center). Widespread faucets use three holes spread 8-16 inches apart.
If you have a single-hole sink and want a faucet with a separate sprayer, that’s not going to fit without drilling. Buy to match what you have unless you’re ready for a bigger project.
Also look at whether you have an existing sprayer hose coming through a fourth hole. If you’re removing that and going to a pull-out or pull-down faucet, the fourth hole needs a cover plate (most faucets include one).
Step 2: Shut Off the Water
The shutoff valves are in the cabinet under the sink. Two valves, one for hot (left) and one for cold (right). Turn them both clockwise until they stop. Open the faucet handles to relieve pressure and drain whatever’s left in the lines. If the valves don’t fully stop the flow, you’ll need to shut off the main. The guide to shutting off water to your house walks through both scenarios.
Place a bucket under the supply connections. Even with valves closed, there’s some water left in the lines.
Step 3: Disconnect the Supply Lines
Under the sink, the supply lines run from the shutoff valves up to the underside of the faucet body. Use channel-lock pliers or an adjustable wrench to turn the nuts counterclockwise. The nuts at the top (where lines connect to the faucet) are usually in a cramped spot. Sometimes you can get an adjustable wrench on them, sometimes you need the basin wrench.
If the lines are older braided stainless, replace them now while you’re already under there. Old plastic-sleeved lines can crack without warning, and a kitchen flood while you’re at work is a bad day.
Step 4: Remove the Old Faucet
This is where the basin wrench earns its price. A basin wrench is a long-handled tool with a pivoting jaw designed specifically to reach the mounting nut that’s typically 6-10 inches behind the sink deck. A Ridgid 2017 or a General Plumbing Supply equivalent runs about $20-30 and saves an enormous amount of frustration.
With the supply lines disconnected, use the basin wrench to loosen the mounting nut counterclockwise. On older faucets, this nut is often plastic and hand-tightens easily. On faucets that have been in place for 10+ years, it’s sometimes seized with mineral scale. Penetrating oil (let it sit 20 minutes) usually handles this.
Once the nut is off, lift the faucet straight up from above the sink. If there’s a base plate gasket, it usually pulls up with it.
Step 5: Clean the Sink Deck
Old faucets leave behind plumber’s putty residue, silicone, or mineral scale on the sink deck. Use a putty knife to scrape off the bulk of it, then wipe down with a rag. The deck should be flat and dry before the new faucet goes down, otherwise the base gasket won’t seal correctly.
While you’re up top, this is also a good time to clean the area around the drain. Getting under the sink is always an adventure, and future-you will appreciate the cleanup.
Step 6: Install the New Faucet
Most modern kitchen faucets install from above. Drop the supply tubes down through the hole(s) in the sink deck, then lower the faucet body into position. If your faucet includes a deck plate (for covering additional holes), set that down first.
From below, thread the mounting nut onto the faucet shank by hand. Snug it with the basin wrench: hand-tight plus roughly a quarter turn. You’re clamping the faucet to the sink deck, not torquing it down. Over-tightening cracks plastic shanks and warps metal ones.
If the faucet came with a weight on the spray hose (for pull-down models), clip it onto the hose before you forget. It sits about 8-10 inches down and keeps the hose retracted properly.
Step 7: Connect the Supply Lines
Wrap two or three layers of plumber’s tape clockwise around the male threads on both supply line ends. This helps the connection seal without over-tightening.
Thread the supply line nuts onto the shutoff valve inlets (hand-tight, then a quarter to half turn with pliers). Connect the top ends to the faucet supply inlets. Many faucets use 3/8-inch female connections at the top; the lines you bought at the hardware store almost certainly match. If something doesn’t thread smoothly, stop and check the sizing rather than forcing it.
While you’re under there, take a look at the P-trap and drain connections. If you’ve been dealing with a slow kitchen drain, this is a convenient moment to address it before closing everything up.
Step 8: Turn On the Water and Test
Open both shutoff valves slowly, about a half turn at a time. Stay under the sink while you do this and watch the supply line connections for drips.
Once the valves are fully open, go up top and run both hot and cold to flush air from the lines. A few seconds of sputtering is normal. Check under the sink again for any moisture around the connections. A dry connection is a good connection.
Check the base of the faucet at the deck too. If water is pooling there, the base gasket may not be seated flat, usually from debris on the deck surface that I mentioned in step 5.
Common Mistakes
Buying the wrong faucet. Not counting holes before shopping is the most common error. A three-hole sink and a single-hole faucet are not an easy adaptation. Measure first, buy second.
Skipping the supply line replacement. Braided stainless lines from major manufacturers are rated for 10-12 years. If yours are older than that, swap them out. At $15, the insurance cost is trivial compared to a kitchen flood cleanup.
Over-tightening the mounting nut. The faucet needs to be snug against the deck, not gorilla-tight. Cracking a plastic shank means a second trip to the hardware store.
Not using plumber’s tape. Bare threads at a compression fitting are asking for a slow drip. Two or three wraps, clockwise on the male threads, every time.
Forgetting the spray hose weight. Pull-down faucets need that counterweight clipped to the hose or the spray head droops and won’t retract. Easy to forget when you’re relieved the job is done.
FAQ
How hard is it to replace a kitchen faucet yourself? It’s a beginner plumbing job with basic tools. The hardest part is usually reaching the mounting nut with the basin wrench in a cramped cabinet. Budget 60-90 minutes for a straightforward swap and add time if the old nuts are seized.
Do I need to turn off the main water supply to replace a kitchen faucet? Only if the shutoff valves under the sink don’t fully stop the flow. Most kitchens have dedicated under-sink valves that work fine. If yours leak past or are corroded, shut off the main first and replace those valves while you’re in there.
What kind of basin wrench do I need for a kitchen faucet? A standard basin wrench with a pivoting jaw is fine for most kitchen faucets. A telescoping model (around $25-35) reaches further for deeper installations. Skip the cheap ones, the jaw slips on corroded nuts and you lose skin on the cabinet floor.
How do I know what size kitchen faucet to buy? Count your sink holes and measure the spacing. Single-hole (1 hole), centerset (3 holes, 4 inches center to center), or widespread (3 holes, 8-16 inches apart). Most faucets also list the deck plate dimensions; make sure it covers any holes you’re not using.
How long should kitchen supply lines last? Most manufacturers rate braided stainless supply lines at 10-12 years, though you’ll find some plumbing forums where people have run them 20 years without failure. The failure mode is usually a slow weep at a ferrule, not a sudden burst, but a kitchen flood is a kitchen flood. Replace them when you’re already under there doing other work.
Can I use a kitchen faucet with a pull-down sprayer if I have a separate spray hole? Yes. The pull-down hose runs through the main faucet hole, and you cover the unused spray hole with a hole cover plate, sometimes called a deck plate or a sink hole cover. Most pull-down faucets include one in the box.
What’s the difference between a kitchen faucet and a bathroom faucet replacement? The overall process is similar, but kitchen faucets sit on a deeper deck with less access from below, which is why the basin wrench matters more. Kitchen supply lines are also typically longer. The bathroom faucet replacement guide covers the bathroom-specific configuration differences.
Is it worth paying a plumber to replace a kitchen faucet? If the under-sink cabinet is packed and the old nuts are seized, the labor is genuinely unpleasant. Most plumbers charge $100-200 for the job (parts extra), and the savings from doing it yourself fund a decent faucet upgrade. The job itself is not technically difficult, just spatially awkward.