How to Install a New Bathroom Sink Faucet
Bathroom faucet install is 60 minutes if you can access mounting nuts. Older cabinets with limited access make it 90 minutes.
TL;DR
Bathroom sink faucets install identically to kitchen faucets but with smaller hardware. Same 7 steps: shut off water, disconnect old faucet, clean sink top, install new faucet, connect supply lines, restore water, test. Basin wrench is essential.
What’s in this guide
- Pre-install checklist
- Tools
- Removal
- Installation
- Test
Bathroom sink faucet installation follows the same procedure as kitchen, just with smaller hardware. Most challenges are access-related — cramped cabinets and short reach distances.
Tools & Materials You’ll Need
Tools
- Basin wrench
- Adjustable wrench
- Screwdrivers
- Penetrating oil
- Bucket
- Towels
Materials
- New faucet
- Braided stainless supply lines ($12)
- Plumber’s putty (some installs)
- Plumber’s tape
Step-by-Step Instructions
Shut Off Water
Close hot and cold supply valves under the sink. Open faucet to relieve pressure.
Disconnect Old Faucet
Disconnect supply lines at faucet. Use basin wrench to loosen mounting nuts above. Remove faucet from above.
Clean Sink Surface
Scrape off old plumber’s putty. Clean with rubbing alcohol.
Position New Faucet
Most modern faucets have base gasket pre-installed. Center on sink, supply tubes through hole(s).
Tighten Mounting Nuts
Hand-tight + 1/4 turn with basin wrench. DO NOT over-tighten.
Connect Supply Lines
Connect new braided stainless supply lines (always replace — never reuse). Hand-tight + 1/4 turn at both ends. Hot to hot, cold to cold.
Test
Slowly open supply valves. Test cold, hot, mix. Check all connections for drips. Wait 30 minutes and recheck.
Always replace supply lines when replacing a faucet. The cracked supply hose under a sink at year 11–13 is a top-5 emergency call we get. New stainless braided lines: $24 for the pair.
Don’t skip supply line replacement
Old supply lines fail catastrophically.
Real Scenarios from Our LA Service Calls
New faucet, old supply
Customer saved supply lines with new install. Year later: failed at 2 AM, flooded bathroom, $1,200 in damage. Lines would have been $24.
When to Call a Plumber Instead
DIY isn’t always the right call. Bring in a licensed plumber if any of these apply:
- Mounting nuts won’t budge
- Sink top damaged
- Touchless or smart faucet (electrical)
Frequently Asked Questions
How long should installation take?
60–90 minutes if access is good. 2 hours for difficult cabinets.
Do I need a basin wrench?
Yes — channel locks won’t reach.
Can I use the old drain stopper?
Yes if compatible. Check matching mechanism type.
Why is my new faucet noisy?
Trapped air. Run hot/cold separately at full flow for 60 seconds.
Premium faucet vs basic?
Premium (Brizo, Grohe) lasts 15–25 years. Basic 5–10. Worth the upgrade.
Need professional help in Los Angeles?
Same-day service. Flat-fee pricing. No surprise add-ons.
Call (818) 938-8660