You can replace a kitchen faucet in two to four hours with basic tools

Replacing a kitchen faucet is a plumbing job you can do yourself if you are comfortable working under a sink and tightening connections. You will need an adjustable wrench, a basin wrench (a specialized tool that costs $10 to $20), a bucket, and towels. The job involves turning off the water supply, disconnecting the old faucet, removing it from the sink, installing the new one, and reconnecting the supply lines. Most people finish in an afternoon without calling a plumber.

The hardest part is usually reaching the nuts under the sink in a tight space, not the plumbing itself. If your sink is old or the connections are corroded, you may run into stuck bolts or cracked supply lines, which can add time. But the basic sequence is straightforward and the same for nearly every faucet.

Key Takeaways

  • Turn off the water supply under the sink before you disconnect anything, and test that the water is off by turning on the faucet.
  • A basin wrench lets you reach the mounting nuts under the sink without removing the entire cabinet, saving hours of work.
  • Disconnect the supply lines by hand first, then use a wrench only if they are stuck; forcing a corroded connection can crack the line.
  • Install the new faucet with the rubber gasket and mounting hardware in the order the manufacturer specifies, or water will leak around the base.
  • Test for leaks at the supply line connections and under the sink before you consider the job done.

Turn off the water and clear the space under the sink

Locate the shutoff valves under the sink. They are usually two small knobs or levers on the hot and cold supply lines coming from the wall. Turn both clockwise (or pull the lever toward you) until they stop. Then turn on the faucet at the sink to release any water still in the lines. If no water comes out, the shutoff worked.

If you cannot find shutoff valves under the sink, or they do not work, you will need to shut off the main water supply to the house. This is usually a valve near the water meter or where the main line enters the house. Once the water is off, open the lowest faucet in the house (usually a basement or outdoor spigot) to drain the lines.

Remove everything stored under the sink — cleaning supplies, trash cans, anything that takes up space. Place a bucket under the faucet connections to catch water that drains from the lines. Lay towels on the floor to catch spills.

Disconnect the supply lines and drain lines

Look at the two flexible hoses (or rigid copper tubes) connected to the faucet. These are the hot and cold supply lines. Loosen the nut where each line connects to the faucet by turning it counterclockwise with an adjustable wrench. If the nut turns easily by hand, unscrew it by hand first to avoid stripping it. Once it is loose enough, finish unscrewing by hand and pull the line away from the faucet.

If a nut is stuck or corroded, explore a penetrating oil (such as WD-40) and wait 10 to 15 minutes before trying again. Do not force it with the wrench — a corroded supply line can crack, and replacing it is more work than waiting for the oil to soak in.

If your faucet has a sprayer hose, disconnect it the same way. Some faucets also have a drain line connection under the sink; if yours does, loosen and remove that as well. Once all connections are loose, you can move on to removing the faucet itself.

Remove the old faucet from the sink

The faucet is held to the sink by mounting nuts on the underside. You will need a basin wrench to reach these nuts in the tight space under the sink. A basin wrench has a long handle and a small head that fits into tight spaces and grips the nut as you turn the handle.

Position yourself under the sink and locate the mounting nuts. They are usually brass or plastic and sit on the threaded posts that come up through the sink. Use the basin wrench to turn each nut counterclockwise. As you loosen them, the faucet will become loose at the top. Once both nuts are loose, push the faucet up and out from above the sink.

If the faucet does not come free, check that all connections are truly disconnected. Sometimes a small hose or bracket is straightforward to miss. Once the old faucet is out, clean the sink surface where it sat. Old caulk or mineral deposits can prevent the new faucet from sealing properly.

Install the new faucet and reconnect the supply lines

Check the manufacturer's instructions for your new faucet. Most come with a rubber gasket, a metal washer, and mounting nuts. The gasket goes on the underside of the faucet first, then the washer, then the nut. Install these in the order the instructions specify — the order matters for the seal.

Lower the new faucet through the holes in the sink. From underneath, slide the gasket onto the threaded posts, then the washer, then hand-tighten the mounting nuts. Use the basin wrench to tighten them fully, but do not over-tighten — you only need them snug enough that the faucet does not move.

Reconnect the hot and cold supply lines to the faucet. Hand-tighten the nuts first, then use the wrench to tighten them another quarter turn. They should be snug but not so tight that you cannot loosen them later if needed. If your faucet has a sprayer or drain connection, reconnect those as well.

Turn the water back on and check for leaks

Turn the shutoff valves under the sink counterclockwise (or pull the lever away from you) to restore water pressure. Turn on the faucet and let it run for 30 seconds. Check the connections under the sink for drips. A small drip at a nut usually means it needs another quarter turn with the wrench. A steady leak from the supply line itself means the line is damaged and needs to be replaced.

Check the base of the faucet where it meets the sink. Water should not pool there. If it does, the gasket may not be seated properly, or the mounting nuts may be loose. Tighten the mounting nuts slightly and test again.

Run hot water for a minute and cold water for a minute to make sure both lines are working. Check under the sink one more time after the water has run. If everything is dry, the job is done.

Common problems and how to fix them

Water leaks from the supply line connection. Turn off the water, loosen the nut with the wrench, and inspect the rubber washer inside the nut. If it is cracked or flattened, replace it. If the washer looks fine, tighten the nut another quarter turn and test again. If the leak continues, the supply line itself may be damaged and will need to be replaced.

Water pools around the base of the faucet. This usually means the rubber gasket is not seated properly. Turn off the water, loosen the mounting nuts under the sink, and lift the faucet slightly. Check that the gasket is centered and not twisted. Push the faucet back down and re-tighten the nuts. If the gasket is damaged, you will need to remove the faucet and install a new one.

The faucet handle is hard to turn or stuck. This is usually a problem with the cartridge or valve inside the faucet, not the installation. Most faucets come with a warranty that covers this. Contact the manufacturer for a replacement cartridge or faucet.

Water pressure is low from one side. Turn off the water and loosen the supply line nut. A small screen or aerator inside the connection may be clogged with sediment. Remove the screen, rinse it, and reinstall it. If that does not work, the shutoff valve under the sink may be partially closed or faulty.

Frequently Asked Questions

Do I need a plumber to replace a kitchen faucet?

No, if you are comfortable working under a sink and using basic tools. The job is mostly about disconnecting and reconnecting supply lines, which do not require a license. If you run into a stuck bolt, a damaged supply line, or a corroded shutoff valve, a plumber can fix those issues, but the basic faucet swap is a homeowner job.

What if I do not have a basin wrench?

You can rent one from a hardware store for $5 to $10, or buy one for $15 to $20. Without it, you will have to remove the cabinet under the sink to reach the mounting nuts with a regular wrench, which adds an hour or more to the job. A basin wrench is worth the cost or rental.

Can I replace the faucet without turning off the water?

No. If you disconnect the supply lines without turning off the water, water will spray out under pressure and flood the cabinet. Always shut off the water first and test that it is off by turning on the faucet.

How long does a new kitchen faucet last?

A mid-range faucet usually lasts 15 to 20 years. Budget faucets may fail in 5 to 10 years. High-end faucets can last 25 years or longer. The lifespan depends on water quality, how often the faucet is used, and whether the cartridge or valve inside is replaceable.

What if the old faucet is caulked to the sink?

Use a utility knife or caulk removal tool to cut away the old caulk before you try to remove the faucet. Once the faucet is out, scrape away any remaining caulk from the sink surface. You will explore new caulk around the base of the new faucet after installation.