A bathroom sink clogged with hair almost always has the plug within reach: on the pop-up stopper, in the first few inches of the tailpipe or in the P-trap under the basin. Remove the stopper, pull the hair out with a drain claw, then flush with hot tap water. If water still sits in the basin, open the trap. For more clog help, see our drain cleaning and clogs hub.
Why does hair clog a bathroom sink drain?
Hair does not dissolve, so it catches on rough pipe walls and on the stopper's pivot rod, then binds with soap, toothpaste and skin oils into a gray mat. The mat starts small and slows the drain for weeks before it stops it. Most bathroom clogs form within a few inches of the basin, where the pipe narrows.
Three spots collect most of the trouble:
- The stopper and its pivot rod. Hair loops around the crossbar under the stopper.
- The tailpipe. The short vertical pipe below the basin, usually narrow.
- The P-trap. The U-shaped bend that holds water to block sewer gas, where the mat settles.
Knowing the spots saves time. You rarely need to snake deep into the wall for a hair clog, so start high and work down.
How do I clear a hair clog from the pop-up stopper?
Pull out or unhook the stopper, wipe off the hair with a paper towel and clear the opening below. Many pop-up stoppers lift straight out. Some need a quarter turn, and others are held by a pivot rod behind the faucet, which you free by loosening a small nut under the sink and sliding the rod out.
- Clear the cabinet under the sink and put a small bucket in place.
- Lift or twist the stopper out. If it will not move, check the pivot rod nut at the back of the tailpipe.
- Wipe the stopper clean. Hair often hangs from it in a wet string.
- Reach into the drain with a flashlight and pull out what you can see.
- Run hot tap water to move the loose scum.
A plastic drain claw, a thin barbed strip you push down and pull out, works well here. It costs a few dollars at a hardware store and pulls up hair that fingers cannot reach. This one step clears a large share of slow basins, as most of the hair sits near the top.
How do I clear the P-trap when water is standing in the basin?
Standing water means the clog is lower than the stopper, so open the P-trap. Put a bucket under it, loosen the two slip nuts by hand or with pliers and lower the trap. Empty it, pull out the hair and gunk, rinse it in another sink and refit the washers and nuts snugly.
Check the pipe going into the wall, too. If hair sits there, a small hand auger helps. A plumber's snake, also called a drain auger, is a slender flexible tool that breaks up or pulls out a clog beyond your reach. Feed it in gently, turn the handle and pull back with the plug on the end. Do not force it, since plastic pipe and old metal fittings can both be damaged.
Refit the trap, run the tap and check each joint for drips. Wipe the joints with a dry paper towel, which shows even a tiny leak. If a nut weeps, tighten it a quarter turn more.
Why is my bathroom sink still clogged after I tried everything?
If the hair is gone and the sink still runs slowly, the clog is farther along, the vent is blocked or the pipes are narrowed by buildup. A drain that gurgles, or that clears and then slows again within days, points beyond the basin. Check if the tub or toilet on the same line is also slow.
What to look at next:
- Other fixtures. If the shower or toilet nearby also drain slowly, the branch line is the problem.
- Gurgling. A sound when water drains can mean a blocked vent pipe.
- Reassembly. Check the trap is not tilted so that water pools in it.
- Rough or worn pipe. Corroded metal pipe inside the wall can trap hair even after the trap is clean.
Older drains can be worn from the inside, and this is where a plumber with a longer cable or a camera can find what a hand tool cannot. If you suspect the main line, our guide on removing a sewer smell explains more.
Should I use chemical drain cleaner on a hair clog?
Avoid it. Chemical drain cleaners are harsh on skin, eyes and lungs, and the National Capital Poison Center warns that products containing lye can cause serious burns. It also advises never to mix cleaning products, because the combinations can release poisonous fumes. Hair clogs also respond poorly to chemicals, because the mat needs removing, not dissolving.
If you already poured a product in, do not plunge, as it can splash back, and tell any plumber who opens the pipe. Wear gloves and eye protection for any follow-up. If someone inhales fumes or is splashed, get to fresh air, rinse with water and call Poison Control at 1-800-222-1222.
A plunger is a safer option for partial clogs. Use a cup plunger with enough water to cover the cup, seal over the drain and block the overflow hole with a damp cloth so the pressure goes down the pipe.
How do I keep hair out of my bathroom sink?
A small mesh strainer over the drain catches hair before it goes down. Clean it every few days, and every month lift the stopper and wipe the pivot rod. A few minutes with a drain claw every couple of months beats a weekend with a bucket and a wrench.
Habits that help: brush hair over the trash, not the basin; wipe shaving residue; and do not wash paint, wax or cooking fat down any sink. For the bathtub, where hair is an even bigger problem, read how to unclog a shower drain.
When should I call a plumber?
Call if the sink drains slowly after you have cleared the stopper and trap, if several fixtures drain badly at once, or if water or sewage comes up elsewhere. Also call if a slip nut is stripped, the pipe is cracked or you cannot get the trap off.
California law needs a contractor license for plumbing work over $1,000 or any job requiring a permit, but a basin clog is a small task and does not. If you want help, ask us through the quote page and we'll arrange a local plumber to come to you. See what a plumber charges to clear a sink for a guide. Our home page shows how a job runs.
Common questions
What is the fastest way to unclog a sink full of hair?
Pull the stopper, take the hair off it and use a plastic drain claw to lift what sits in the drain opening, then flush with hot tap water. This clears most bathroom sinks in ten to fifteen minutes. If water still stands, take off the P-trap over a bucket and clean it.
Does boiling water clear hair from a drain?
Not by itself. Hot water can loosen soap and oil, but it does not dissolve hair, and boiling water can soften PVC joints or crack a porcelain basin. Use hot tap water after you have removed the hair mechanically. For a stubborn plug, a drain claw or trap clean will do more than any liquid.
Why does my bathroom sink drain slowly even with no hair?
Soap scum, toothpaste and mineral buildup can narrow the pipe over time, so the sink drains slowly without a visible plug. A vent blockage can also slow it and cause gurgling. Clear the trap, run hot water and, if it persists, ask a plumber to snake or camera the line.
Can a plunger clear a bathroom sink?
Yes, for light clogs. Use a small cup plunger, add water to cover the cup, plug the overflow with a damp cloth and push and pull steadily. Hair mats often need pulling out, not pushing, so a plunger may only loosen them. Follow with a drain claw or by opening the trap.
How much does a plumber charge to clear a bathroom sink?
Costs vary with the plumber and the clog, so ask for a written quote first. Published guides show a call-out fee and an hourly rate, with a simple sink clearing often taking under an hour. Our cost guide has more, and the plumber we arrange quotes the real price after a look.