To replace a bathroom sink faucet, shut off water, remove old hardware, set the new faucet, connect lines, then test and check for leaks.
Swapping in a new faucet freshens up the vanity and stops nagging drips. This guide walks you through every stage—from choosing the right fit to sealing, tightening, and flushing the lines—so you finish with a clean, drip-free install.
How To Replace A Bathroom Sink Faucet: Tools And Prep
Gather tools first so you aren’t crawling in and out of the cabinet. A basic kit covers most models: adjustable wrench, basin wrench, bucket, towels, putty knife, rags, flashlight, PTFE thread tape for threaded fittings, silicone or plumber’s putty (as the faucet maker specifies), and new supply lines if the old ones look worn. Keep a small cup handy to catch leftover water in the lines.
| Situation | What To Check | What To Buy |
|---|---|---|
| 4″ Centerset (3 holes, 2"–4" spread) | Three holes close together; baseplate often covers them | Centerset faucet; optional deck plate |
| Widespread (8"–16" adjustable) | Three holes spaced wider; separate handles | Widespread faucet set; measure spread |
| Single-Hole | One hole only | Single-hole faucet; escutcheon if extra holes need covering |
| Old Metal Supply Lines | Corrosion, kinks, outdated connectors | New braided stainless supply lines (match length & size) |
| Pop-Up Drain Included | Rod or click-pop style in box | Use included drain; plumber’s putty or gasket per manual |
| Countertop Material | Stone can stain from oil-based compounds | Use silicone where manuals prohibit putty on stone |
| Low-Flow Preference | Save water without a weak stream | WaterSense-labeled bathroom faucet or aerator |
| No Shutoff Valves | Cabinet lacks hot/cold stops | Add angle stops before installing the faucet |
Step-By-Step: Remove The Old Faucet
1) Kill The Water And Depressurize
Turn the hot and cold stop valves clockwise until they stop. Open the faucet to bleed pressure. If a valve won’t close, shut off the home’s main and plan on replacing the sticky stop later.
2) Disconnect Supply Lines
Place a bucket under the valves. Loosen the nuts at the shutoffs, then the nuts at the faucet tails. Expect a small splash as the lines drain. If the lines look brittle or kinked, replace them now.
3) Free The Old Hardware
Slide a basin wrench onto the hard-to-reach mounting nuts under the faucet. Back them off, cut old sealant at the rim with a putty knife, and lift the faucet out. Clean the deck until it’s smooth and residue-free.
4) Remove Or Rebuild The Drain
Unscrew the P-trap and remove the old drain body if you’re installing a new one. Set a towel in the cabinet to protect it from scuffs and drips. Keep track of gaskets and the pop-up rod parts if reusing them.
Fit And Seal The New Faucet
5) Dry-Fit The Body And Escutcheon
Before sealing, test how the faucet sits. Confirm the handles clear the backsplash and the spout centers over the bowl. Thread the tails through the deck and verify the gasket or plate covers the holes.
6) Seal The Base
Follow the faucet manual for the correct sealant. Many centerset and widespread bases use a rubber gasket; some call for a thin bead of silicone; older styles call for plumber’s putty under the trim. If you’re on natural stone, use a non-staining option the manufacturer allows.
7) Tighten The Mounting Hardware
From below, install the washers and nuts. Snug the fasteners evenly. Recheck alignment above the deck and finish tightening by hand plus a small wrench turn. Don’t crush the sink or deform the gasket.
8) Connect The Supply Lines
Hand-thread the lines to the faucet tails first to avoid cross-threading, then to the shutoffs. Compression and flat-gasket connections typically do not need thread tape; threaded pipe fittings do. Tighten until snug; add a small turn if a drip appears during testing.
Install The Pop-Up Drain (If Included)
9) Seat The Flange
Roll a rope of plumber’s putty (unless the manual specifies a gasket or silicone) and form a ring under the drain flange. Press the flange into the sink’s drain hole from above.
10) Lock The Body And Gaskets
From below, slide on the rubber gasket and nut. Align the drain’s rod opening toward the rear. Tighten until the flange feels solid. Wipe away squeezed-out compound at the rim.
11) Assemble The Pop-Up
Insert the stopper, connect the pivot rod, clip it to the lift rod strap, and test the motion. Adjust the strap hole so the stopper seals snugly but still pops up freely.
Turn Water Back On And Flush
12) Pressure Test
Close the faucet handles. Crack open each stop valve half a turn, listen for flow, then open fully. Check all joints with a dry tissue; even a pinhole drip will show up. Tighten as needed.
13) Flush Aerator And Lines
Unscrew the aerator, run hot and cold for 30–60 seconds to clear debris, then reinstall the aerator. This prevents trapped grit from clogging the new cartridge.
Pick The Right Sealant For The Job
Sealants aren’t one-size-fits-all. Many faucet bases rely on a molded gasket alone. Some trim rings and drains prefer plumber’s putty for easy future service. Silicone bonds firmly, which is helpful on certain stone tops and where the manual calls for it. Always follow the brand’s sheet included in the box for the exact method.
Smart Upgrades While You’re There
Swap Old Stops And Lines
If the shutoff valves grind or the handles wobble, replace them. New angle stops and braided stainless supply lines are inexpensive and add peace of mind.
Choose A Water-Saving Faucet
A WaterSense-labeled bathroom faucet trims water use while keeping a strong feel at the tap. Look for the label when shopping and you’ll curb waste without a sluggish stream.
Safety, Access, And Fit Tips
Clearance Behind The Spout
Measure from the hole to the backsplash. Tall single-handle models with rear lift rods need extra room. If space is tight, pick a faucet with a click-pop drain that doesn’t use a rear rod.
Countertop And Sink Stability
Thin sinks flex when over-tightened, which can lead to drips later. Snug hardware evenly and stop when the base seals all around. If the sink shifts inside a vanity cutout, shim and secure the bowl before you begin.
PTFE Tape Basics
Wrap thread tape clockwise on male tapered threads only. Don’t tape compression threads or gaskets. Two to three wraps usually seal well; more can bunch up and prevent a tight seat.
Time And Cost
Most replacements land in the 60–120 minute range for a typical centerset faucet and drain. Expect quicker swaps if you have flexible lines, room to work, and no corrosion. Widespread sets add extra minutes for alignment and separate valves.
Troubleshooting After Installation
Minor Drip At A Supply Nut
Give the nut a small turn. If it still weeps, shut water off, disconnect, check the ferrule or gasket, and reconnect. Replace a cracked supply line on sight.
Base Leaks When Running Water
Recheck the deck gasket or sealant ring. The base must sit flat with even pressure. If putty was used on stone, swap to a non-staining seal per the faucet manual and reset the trim.
Weak Flow On One Side
Debris can lodge at the aerator or cartridge. Remove the aerator and flush again. If needed, close stops, remove the handle for that side, pull the cartridge, rinse, and reinstall.
Common Problems And Fast Fixes
| Symptom | Likely Cause | Quick Fix |
|---|---|---|
| Drip At Handle | Debris in cartridge | Flush lines; reseat or replace cartridge |
| Leak Under Deck | Loose mounting or bad seal | Retighten evenly; reset base with correct sealant |
| Poor Pop-Up Seal | Rod misadjusted; gasket out of place | Move clip to a new hole; reseat gasket |
| One Side Weak | Shutoff not fully open; clogged aerator | Open valves; clean aerator; flush |
| Supply Nut Weeping | Cross-threaded or over-taped | Reconnect carefully; tape only tapered threads |
| Backsplash Interference | Handle hits wall | Rotate base slightly or pick a compact model |
| Stiff Stop Valves | Old angle stops sticking | Replace stops; test before reconnecting |
Model-Specific Notes That Save Time
Manufacturers include model-specific steps—gasket order, washer orientation, and torque guidance—that differ by trim. Keep the instruction sheet within reach. Some sets also include a quick-connect hose joining the hot and cold bodies to the spout; push until it clicks and tug lightly to confirm engagement.
Care And Maintenance
Wipe water spots after showers so minerals don’t build up at the base. Unscrew and clean the aerator any time flow feels off. If your water is hard, soak the aerator in warm white vinegar for a few minutes, rinse, and reinstall. Light valve squeak often clears after cycling the handle a few times post-flush.
When To Call A Pro
If shutoff valves won’t close, if supply connections are corroded solid, or if you see movement in the sink or countertop, pause and bring in a plumber. Fixing a seized stop or a loose sink while everything is apart turns a tough evening into a one-and-done repair.
Where This Guide Fits Your Search
You came here to learn how to replace a bathroom sink faucet without guesswork. You now have the prep list, two sealing paths that match common manuals, clear steps, and fast checks when something doesn’t go right. Use the tables for quick decisions and the step list when you’re under the cabinet.
When shopping, look for the WaterSense bathroom faucet label to trim water use with a strong stream. For a common 4-inch centerset layout, see a typical manufacturer installation sheet for gasket order and tightening sequence.
Bookmark this walkthrough so the next time someone asks how to replace a bathroom sink faucet, you’ll have a reliable, step-by-step reference that works across most brands.