RUSign in

Slow Bathroom Sink Drain: How to Clear It Without Chemicals

Nine times out of ten a slow bathroom sink is a clump of hair and soap scum wrapped around the pop-up stopper or sitting just below it. You can clear it from above in minutes. Chemical drain cleaners rarely dissolve hair and can harm old pipes and your hands.

Verdict: DIY

Easy and cheap. Skip the chemical drain cleaners, they damage pipes and don't remove hair well.

Time
10–30 min
Cost
$0–10

Likely causes and how to tell

  • Hair and soap at the stopper

    The sink drains slowly but eventually empties; you see gray gunk when you lift the stopper.

  • Clog in the P-trap

    Clearing the stopper didn't help. The U-shaped pipe under the sink holds debris.

  • Clogged overflow or vent

    The drain gurgles loudly, or several fixtures drain slowly at once (then it's further down the line).

How to fix it

  1. 1

    Pull the stopper

    Many stoppers lift straight out or twist a quarter turn. If not, loosen the pivot nut on the back of the drainpipe under the sink and slide the rod out, then lift the stopper.

  2. 2

    Use a drain snake tool

    Push a plastic barbed drain stick ($3) down the drain, twist and pull up. Repeat until it comes up clean.

  3. 3

    Flush with hot water

    Run hot tap water for a minute. Avoid boiling water on PVC pipes.

  4. 4

    Clean the P-trap if still slow

    Put a bucket under the trap, unscrew the two slip nuts by hand, empty and rinse the trap, and reinstall hand-tight plus a quarter turn.

  5. 5

    Reinstall the stopper

    Reconnect the pivot rod through the stopper's hole and tighten the pivot nut. Check for drips under the sink.

What you'll need

  • Plastic drain snake (barbed stick)
  • Bucket
  • Rubber gloves
  • Adjustable pliers

Call a pro if

  • Several drains in the house are slow or back up at the same time (main line clog).
  • Sewage smell or water comes up in a tub or shower when you run the sink.
  • Old metal pipes are corroded and crumble when you touch the slip nuts.

AI Handyman writes a free job brief in trade language, so a pro can quote from your photos.

Questions people ask

Do baking soda and vinegar work?

They can freshen a drain, but they rarely clear a hair clog. A $3 drain stick is faster and more reliable.

Is chemical drain cleaner safe?

It can damage older pipes and is dangerous if it splashes. If you've already poured some in, tell the plumber before they open the pipes.

Related fixes

General guidance, not a licensed inspection. Follow local codes; when in doubt, call a licensed professional.