Bathtub Won't Drain
Updated February 20, 2026
Tub draining slow or holding standing water? Almost always a hair clog in the stopper, crossbar, or P-trap. Soap scum and conditioner cement it into a dense mat. Clearable in under 30 minutes.
Overview
Tub drains clog more than almost any other fixture, and hair is almost always the culprit. It catches on the stopper, crossbar, or inside the P-trap, and soap scum cements it into a sticky mat that gets worse over time. First you notice slow draining during showers. Eventually it is standing water. The fix depends on where the clog is -- stopper, drain shoe, P-trap, or branch line. This guide goes from simplest to most involved.
Symptoms
- Water pools around your feet during a shower and drains slowly after you turn off the water
- Tub takes minutes or longer to fully empty after a bath
- Gurgling from the drain as it empties -- air struggling past a partial clog
- Water backs up into the tub when you run the bathroom sink (they often share a branch drain)
- Musty or stale smell from the drain -- decomposing hair and soap trapped in the clog
Common Causes
- Hair on the stopper and crossbar -- the cause of most tub clogs. Hair wraps around the stopper mechanism and crossbar, catches more hair, and soap scum cements it into a solid plug.
- Soap scum and product buildup in the P-trap -- conditioner, body wash, and oils coat the pipe interior, narrowing the diameter and creating a sticky surface that traps everything.
- Misaligned stopper mechanism -- trip-lever and pop-up drains use a linkage inside the overflow tube. If it slips out of adjustment, the stopper sits partially closed even when you think it is open. Common in older tubs.
- Blockage in the branch drain -- if the clog is not at the stopper, crossbar, or P-trap, it may be downstream in the line connecting the tub to the main stack. Years of buildup or objects that fell down the drain.
- Hard water mineral deposits -- calcium and lime forming inside the drain pipe, gradually narrowing it. A slow problem that makes other clogs worse.
What You'll Need
How to Fix It
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Remove and Clean the Drain Stopper
Easiest fix first. Remove the stopper -- method depends on the type. Lift-and-turn: unscrew counterclockwise. Push-pull: pull straight up. Toe-touch: unscrew by hand. Pop-up: remove the overflow plate and pull the linkage out. You will likely find a hair ball wrapped around the stopper shaft and crossbar. Pull it all out with fingers or needle-nose pliers. This alone fixes it in many cases.
Tip: Plastic bag or paper towel ready. The hair ball from a tub drain is one of the more unpleasant things in DIY plumbing. Coated in soap scum and it will smell. -
Use a Zip-It Tool or Drain Snake
Stopper clean but still slow? Zip-it tool ($3-5, barbed plastic strip) or a small drain snake. Push the zip-it straight down as far as it goes, pull out slowly -- barbs catch hair and drag it up. Repeat until it comes out clean. Deeper clog? 15-25 foot drain snake. Feed in while turning clockwise. Resistance = clog. Keep cranking to break through or hook it, pull back out.
Tip: Zip-it tools are disposable and incredibly effective for hair within the first 12-18 inches. Keep a few on hand -- single best tool for routine tub maintenance. -
Try the Baking Soda and Vinegar Method
Good follow-up after pulling hair. Half cup baking soda into the drain, half cup white vinegar. Cover with a wet cloth to force the fizz downward. Wait 30 minutes, flush with a full kettle of hot water. Dissolves soap scum and loosens remaining debris on the pipe walls. Safe for all pipe types.
Warning: Skip chemical drain cleaners (Drano, Liquid-Plumr) in a tub. If the clog does not clear, you have a tub full of standing caustic water to deal with. Chemical cleaners also damage metal pipes, rubber gaskets, and septic systems. -
Check the Trip-Lever Linkage (If Applicable)
Trip-lever drain (lever on the overflow plate)? The linkage may be out of adjustment. Remove the overflow plate (two screws), pull the linkage out. Rod and plunger or rocker arm at the bottom. Clean off hair and debris. Drain not opening fully? Turn the threaded rod to shorten it slightly (raises the plunger, opens the drain more). Reinstall and test.
Tip: With the linkage out, shine a flashlight down the overflow opening. You may spot a clog in the tee fitting where the overflow meets the drain shoe -- a hidden spot the zip-it cannot reach from above. -
Plunge the Tub Drain
Still clogged? Plunging. Fill the tub 3-4 inches. Block the overflow with a wet rag held firmly (prevents pressure from escaping). Cup plunger over the drain, good seal, 15-20 vigorous strokes. Alternating pressure and suction dislodges clogs deeper in the P-trap or branch drain.
Tip: Cup plunger (flat bottom), not a flange plunger. The flat cup seals better on the tub surface. -
Access and Clean the P-Trap (If All Else Fails)
If nothing has worked, the clog may be in the P-trap. Tub P-traps sit below the floor -- access from the basement, crawl space, or an access panel behind the wall. If you can reach it: bucket underneath, loosen slip nuts, remove the trap, clean it out, reassemble. P-trap not accessible (concrete slab, inaccessible ceiling)? This is where calling a plumber with a power snake makes more sense.
Warning: Some tub P-traps are glued, not slip-joint. Glued PVC or cemented ABS means you cannot remove the trap without cutting pipe. Leave that to a plumber.
When to Call a Pro
Call a plumber if the clog does not clear after pulling hair, snaking, and plunging, if multiple bathroom fixtures are slow (branch or main line issue), if you cannot access the P-trap, if water backs up from other fixtures, or if clogs keep returning every few weeks despite cleaning (may be a bellied pipe collecting debris).
Prevention Tips
- Hair catcher over the drain ($5 or less) -- single most effective prevention. Clean it after every shower.
- Clean the stopper once a month. Pull off any hair wrapped around the shaft and crossbar.
- Run hot water 30 seconds after every shower to flush soap residue before it hardens on the pipe walls.
- Monthly baking soda flush (half cup followed by hot water) as preventive maintenance.
- Long hair or multiple people sharing? Clean the hair catcher daily. The accumulation rate is surprising.
- Keep bar soap fragments out of the drain. They dissolve slowly and create sticky residue that speeds up clog formation.