About 80 percent of the time, you can fix slow-draining or clogged tub drains in five minutes, without chemicals and without a $100 plumber bill. In most cases, you'll only need a screwdriver and a stiff wire or a bent coat hanger. The problem is usually just a sticky wad of hair that collects on the crossbars, a few inches under the stopper. All you need to do is figure out how to remove the stopper (that's almost always easy) and fish out the gunk. Bend a little hook on the end of the stiff wire with a needle-nose pliers and shove it through the clog—you'll nearly always extract the entire ugly mess. If hair is wrapped around the crossbars, slice through it with a utility knife and then grab it with the wire.
Follow our series of photos to determine which type of stopper you have and how to remove it.
These stoppers lock and seal when you press them down and release when you push down a second time. The way to remove them isn't so obvious. In most cases you have to hold the stem while unscrewing the cap as shown. With the cap off, you can sometimes fish out the hair from the crossbars. Otherwise simply remove the entire shaft by unscrewing it. You may have to adjust the screw tension on the stem when you reinstall everything to get a good seal.
Many tubs, certainly most older ones, have a stopper located inside the drain and overflow tube. Most of these have a lever on the overflow plate and a screen over the drain. The screen keeps most hair out of the drain, but some gets through and eventually forms a clog at the crossbars. Simply unscrew the screen for easy access to this clog and remove it as before. If the drain has an internal stopper, simply unscrew the overflow plate and pull the linkage and stopper up and out. Then clean the linkage and stopper and run water down the drain to flush it out.
Occasionally the linkage is out of adjustment and the stopper doesn't open far enough from its seat to allow a good flow. Adjust it, reinsert it and test it. Run water into the tub. If it leaks out, lengthen the stopper linkage to seal the drain better. If the drain doesn't open to let the water out, shorten the stopper linkage.