Of all the plumbing jobs homeowners attempt themselves, replacing a kitchen or bathroom faucet has one of the best ratios of visible payoff to actual difficulty. There is no soldering, no cutting into walls, and the entire job is reversible if something goes wrong. The main requirements are patience, the right tools, and a clear sense of the order of operations.

What you will need

  • New faucet (check the box confirms it fits your sink's hole configuration — single hole, or 3-hole/8-inch spread)
  • Adjustable wrench or basin wrench (a basin wrench makes reaching rear nuts far easier)
  • Plumber's putty or the faucet's included gasket
  • Bucket, towels, and a flashlight
  • Plumber's tape (PTFE tape)

Step 1: Shut off the water and clear the space

Under the sink, turn the two shutoff valves clockwise until they stop — one for hot, one for cold. If your sink has no individual shutoffs, you will need to shut off the main water supply to the house. Open the faucet at the top briefly to confirm the water is off and to release pressure in the lines, then place a bucket underneath to catch any residual water. Clear out everything stored under the sink; you will need the full space to work, and you will be lying on your back looking up into it.

Step 2: Disconnect the old faucet

Using the adjustable wrench, disconnect the supply lines from the shutoff valves first, then from the faucet tailpieces. Have a towel ready — there is almost always a small amount of water left in the lines. Next, locate the mounting nuts holding the faucet to the underside of the sink; this is where a basin wrench earns its cost, since these nuts sit in a tight, awkward space that a standard wrench often cannot reach. Loosen and remove them, then lift the old faucet out from above.

Take a moment here to clean the sink surface where the old faucet sat. Years of mineral buildup and old plumber's putty tend to accumulate, and a clean, flat surface helps the new faucet's gasket seal properly.

Step 3: Prepare and place the new faucet

Most modern faucets use a rubber gasket rather than plumber's putty, which simplifies this step considerably — check your specific model's instructions. Feed the faucet's supply lines and mounting hardware down through the sink holes from above, then go back underneath to thread on the mounting nuts or mounting bracket, following the manufacturer's instructions exactly, since mounting hardware varies more than almost any other part of this job.

Hand-tighten first, then snug with a wrench — firm but not aggressive. Over-tightening can crack the faucet base or strip the mounting hardware, which turns a two-hour job into a much longer one.

Step 4: Reconnect the water supply

Wrap the threads on the shutoff valves with two or three turns of plumber's tape if they are not already sealed, then reconnect the supply lines to both the valves and the faucet tailpieces. Hand-tighten, then use the wrench for a final quarter-turn — tight enough to prevent leaks, not so tight that you strain the fitting.

Step 5: Test before you celebrate

Turn the shutoff valves back on slowly and watch every connection point closely for the first minute — this is the single most important step in the entire process, and skipping it is how small drips turn into cabinet damage discovered weeks later. Run the faucet on hot and cold, check the sprayer if it has one, and look underneath again after five minutes of normal use.

The job rarely fails at the faucet itself. It fails at a connection someone tightened by feel instead of checking with a flashlight.

When to actually call a plumber

This project is well within reach for a first-time DIYer when the existing plumbing and shutoff valves are in good working condition. It becomes a different job — one worth hiring out — if your shutoff valves are corroded or will not turn, if there is any sign of existing water damage under the sink, or if you are changing the number or spacing of holes in the sink itself, which usually requires cutting or a new sink altogether. Recognizing that line in advance saves far more time than pushing through a job that has quietly become a bigger one.