How to Install a Kitchen Sink (Drop-In and Undermount)

A kitchen sink installation takes most DIYers 2 to 4 hours and costs $380 to $1,400 if you hire it out. The job breaks into three parts: pull the old basin, seat and secure the new one, then reconnect the drain, disposal, and supply lines. Drop-in models are the easiest swap; undermount sinks need more clamping and a longer sealant cure.

What tools and materials do you need to install a kitchen sink?

A basic sink installation needs hand tools you likely own plus two sealants: a tube of 100% silicone and a stick of plumber’s putty. Add mounting clips (usually packed with the sink), a new basket strainer, and a P-trap kit. Buy the strainer and trap new, because old parts rarely reseal cleanly.

Drop-in vs undermount: which sink install fits your counter?

Drop-in (top-mount) sinks drop into the cutout and rest on a visible rim, so they work on any counter and install in a couple of hours. Undermount sinks mount below the counter for a clean, wipe-straight-in edge, but they need a solid stone or quartz top and hang from clamps, which makes the job slower and pricier.

How do you remove the old kitchen sink?

Removing the old basin comes first and takes about 30 minutes. Shut off the hot and cold stops under the cabinet, open the faucet to drain pressure, then disconnect the supply lines, trap, disposal, and dishwasher hose. Cut the old rim seal so the sink lifts free without chipping the counter.

1. Turn off both angle stops under the sink, then open the faucet to relieve pressure.
2. Place a bucket under the trap and disconnect the P-trap slip nuts.
3. Unplug and unwire the garbage disposal, or twist it off its mounting ring.
4. Disconnect the 3/8 in supply lines from the faucet shanks with a basin wrench.
5. Release the mounting clips under the rim, turning each counterclockwise.
6. Slice the old silicone or caulk bead around the rim with a utility knife.
7. Push up from below and lift the sink out, then scrape the counter clean.

How to install a kitchen sink step by step

Complete the sink installation on the bench before it goes in the counter: mount the faucet, drain, and disposal flange while you have full access. Then dry-fit the basin, seal it, and secure it. Working top-down like this keeps you out of the cramped cabinet for the parts that fight you most.

1. Test-fit the new sink in the cutout. Confirm it sits level and the drain lines up with the waste arm.
2. With the sink upside down on a towel, replace the kitchen faucet and attach the supply lines while access is easy.
3. Seat the basket strainer: press a 1/2 in rope of plumber’s putty under the flange, drop it in, then tighten the locknut from below.
4. Attach the garbage disposal mounting ring to the strainer opening now, per the disposal’s manual.
5. For a drop-in, run a continuous 1/4 in bead of 100% silicone around the underside of the rim.
6. Lower the sink squarely into the cutout and press down so the bead squeezes out evenly.
7. Hook the mounting clips under the counter lip and tighten them in a cross pattern until snug, not cranked.
8. Wipe excess silicone with a damp finger for a clean rim line, then let it cure 24 hours before heavy use.

For an undermount basin, skip the rim clips. Support the sink from below with a brace, run silicone along the top edge, press it to the counter underside, and lock it with the epoxy clamps the fabricator anchored to the stone.

How do you hook up the drain, disposal, and supply lines?

With the basin fixed, reconnect the plumbing in the cabinet: supply lines to the stops, then the drain tailpiece into the P-trap, then the disposal and dishwasher. If you want a refresher on how the tailpiece, trap, and branch drain fit together, see the under-sink plumbing layout.

• Supply lines: thread the 3/8 in braided lines onto the angle stops and faucet shanks. Hand-tighten, then a quarter turn with pliers. Match hot to the left, cold to the right.
• Drain and trap: connect the tailpiece to the P-trap with 1.5 in slip nuts and nylon washers. Snug by hand plus a light turn; overtightening cracks the plastic.
• Garbage disposal: mount the unit to the ring and lock it, then run its discharge to the trap. Knock out the dishwasher plug if a dishwasher drains through it.
• Dishwasher hose: clamp it to the disposal nipple or the drain branch, with a high loop or air gap as your local code may require.

How do you test a new sink for leaks?

Test in stages so a leak is easy to trace. Open the shutoff valves and check every supply joint dry first, then fill both basins and release the water to load the drain and trap. Watch each connection for 5 minutes and run the disposal and dishwasher through a full cycle.

1. Open the angle stops slowly and feel each supply connection for moisture.
2. Turn on the faucet and check the base and shanks. A drip here often means the faucet, so fix a leaky faucet before blaming the sink.
3. Plug both basins, fill them, then pull the stoppers to flood the drain and trap at once.
4. Shine a light on every slip nut and the strainer locknut. Tighten a quarter turn if you see beading.
5. Run the disposal with water, then start the dishwasher and watch the drain hose connection.

How long does sink installation take and what does it cost?

A drop-in replacement takes a pro about 2 hours and a first-timer 4 to 6 hours. Nationally, professional kitchen sink installation runs $380 to $1,400, with most homeowners paying $700 to $900. The basin itself sets the range, from $100 stainless to $900-plus copper or fireclay, and undermount adds 20 to 40 percent.

Frequently asked questions

Can I install a kitchen sink myself?

Yes. A drop-in sink swap is an intermediate DIY job if you can work in a tight cabinet and follow instructions. Budget 2 to 4 hours for your first one. Undermount sinks are harder because the basin hangs from the counter and needs clamps plus a full silicone cure, so many homeowners hire those out.

Do you use plumber’s putty or silicone on a kitchen sink?

Use both, in different spots. Roll plumber’s putty under the drain strainer flange, where a firm non-hardening seal works best. Run a bead of 100% silicone around the sink rim where it meets the countertop, because silicone bonds and stays flexible under standing water. Check your sink’s manual, since some composite basins require silicone at the drain too.

Can you replace a kitchen sink without replacing the countertop?

Usually yes, if the new sink matches the existing cutout. Replacing a drop-in with another drop-in of the same dimensions almost always works because the rim hides small gaps. A larger basin can sometimes be cut in, but going smaller, or switching to undermount on laminate, often means a new counter.

How long does it take to install a kitchen sink?

A straightforward drop-in replacement takes a pro about 2 hours and a first-time DIYer 4 to 6 hours. New construction or a switch to undermount runs longer, sometimes a full day, because of clamping and the 24-hour silicone cure before heavy use. Disposal and dishwasher hookups add 30 to 60 minutes.

What holds a kitchen sink in place?

A drop-in sink is held by its own weight on the rim, a bead of silicone, and mounting clips that hook under the counter and tighten against the underside. An undermount sink hangs from epoxy or clips anchored to the stone, plus a silicone seal. The faucet and drain connections do not support the basin.

How much does it cost to install a kitchen sink?

Kitchen sink installation runs $380 to $1,400 nationally, with most homeowners paying $700 to $900 for a mid-range basin and standard labor. The sink itself is $100 for basic stainless up to $900 or more for copper or fireclay. Plumbers charge $50 to $200 per hour, and undermount adds 20 to 40 percent.

Last reviewed: September 2026.