Bathroom Sink Draining Slowly? How to Fix It

What you'll need

• Rubber gloves
• Needle-nose pliers or an old toothbrush
• Bucket (if you go as far as the P-trap)
• Plastic zip drain tool ($3–$5, optional but handy)
• Baking soda and white vinegar (optional, for a finishing flush)
• Old towels

Step-by-step

1. Start with the stopper. Most pop-up stoppers lift straight out; some unscrew counterclockwise, and a few are held by a pivot rod underneath (squeeze the spring clip to release it). This is where the clog lives 90% of the time.
2. Clean the stopper thoroughly. Pull off the matted hair, soap scum, and toothpaste residue wrapped around it. An old toothbrush gets into the grooves. You'll be mildly horrified — that's normal, and that's the clog.
3. Clean the drain opening. With the stopper out, reach into the drain mouth with the toothbrush or a rag and wipe the gunk ring just inside. Shine a flashlight down — if you see more hair just out of reach, grab it with the pliers.
4. Go deeper with a zip tool if needed. If drainage is still slow, feed a plastic zip tool (those barbed strips) down the drain, wiggle it, and pull it out slowly. It grabs hair from the first several inches where fingers can't reach. A straightened wire hanger works in a pinch.
5. Flush with hot tap water. Run the hottest water from the tap for a couple of minutes. Use hot tap water, not a kettle of boiling water — boiling water can crack porcelain sinks and damage PVC pipe joints.
6. Optional: baking soda and vinegar finish. Pour half a cup of baking soda down the drain, follow with half a cup of vinegar, let it fizz for 15 minutes, then flush with hot water. It's mild — it won't dissolve a real clog, but it freshens things up after the mechanical cleaning.
7. If still slow: check the P-trap. Put the bucket under the curved P-trap beneath the sink, unscrew the slip nuts by hand (they're designed to loosen without tools), and dump out the trap. Clear any sludge, rinse it, and reinstall — hand-tighten the nuts, then a small snug with pliers. Don't overtighten plastic nuts; they crack.
8. Test and prevent. Fill the basin and release it — it should drain briskly. Going forward, a $3 mesh drain strainer catches hair before it starts, and wiping toothpaste residue instead of rinsing it all down the drain slows buildup considerably.

<div class="safety"> <strong>🛑 Stop and call a pro if:</strong> <ul> <li>Multiple sinks or the tub are also draining slowly — a single slow sink is a local clog, but several at once suggests a branch or main line issue.</li> <li>The P-trap or drain pipes are corroded and crumble when touched — old metal traps can disintegrate, and then you're into pipe replacement.</li> <li>Water backs up into the sink from below when other fixtures drain — that signals a blockage deeper in the system, potentially the sewer line.</li> <li>There's a sewage smell that doesn't go away after cleaning — the trap may not be holding water (a venting problem) or there's a leak you can't see.</li> </ul> </div>

DIY vs pro cost

A plumber will do exactly what this guide describes — pull the stopper, clear the hair, maybe pop the trap — and charge a service minimum for it. Twenty minutes of your time versus a $150 bill.

Printable checklist

• [ ] Pop-up stopper removed (lift, unscrew, or release pivot rod)
• [ ] Hair and scum cleaned off the stopper completely
• [ ] Drain mouth wiped clean just inside the opening
• [ ] Zip tool used for deeper hair if still slow
• [ ] Hot tap water flush (not boiling) for 2 minutes
• [ ] P-trap removed, emptied, and reinstalled if needed
• [ ] Basin fill-and-release test drains briskly
• [ ] Mesh strainer placed to prevent the next clog