How to Install a Drain Strainer

Drain clogs are almost always hair, soap scum, and debris—not a pipe problem. The fastest fix is prevention: a drain strainer sits right at the opening of your drain and catches everything before it travels down. Install one in the bathroom sink where hair accumulates fastest, in the shower or tub, and in the kitchen sink if you're not running a garbage disposal. The strainer doesn't eliminate clogs entirely, but it cuts them by 80 percent. You'll spend 5 minutes installing it now and save yourself hours of plunging or costly service calls later. Drain strainers come in a few styles: basket strainers (removable cups with holes that sit in the drain), pop-up strainers (the lever-activated kind in sinks), and simple mesh screens (thin covers that sit on top). For most residential bathrooms and kitchens, a basic basket strainer is the default choice. It's inexpensive, durable, and does the job without adding complexity to your plumbing.

1. Measure First, Buy Second. Use a ruler or flexible measuring tape to measure the diameter of the drain opening from rim to rim. Standard drains are either 1.25 inches or 1.5 inches. If your drain is an unusual size or shape, bring a photo to the hardware store. This measurement ensures you buy a strainer that fits without gaps.
2. Pick the Right Strainer. For bathroom sinks and shower/tub drains, buy a simple basket or dome strainer—the removable cup with holes. For kitchen sinks with a garbage disposal, skip the strainer or buy a thinner perforated model that won't block the disposal's opening. For clawfoot or vessel sinks, verify compatibility before checkout. The strainer should cost $3–$8.
3. Clear the Opening. Remove any visible hair, soap, or debris from the drain opening using your fingers or a paper towel. You don't need to plunge or snake the drain—a quick surface clear is enough. The strainer sits at the top and doesn't require a clear pipe below it.
4. Flush the Drain. Run hot water down the drain for 10–15 seconds to flush loose debris and to wet the drain surface. This helps the strainer seat evenly and shows you whether water is draining at normal speed. If it's sluggish, you may have a clog downstream—address that before installing the strainer.
5. Dry Everything. Use a clean dry cloth or paper towel to wipe the rim of the drain opening. A wet surface causes the strainer to shift or sit unevenly. A one-second wipe ensures a snug, stable fit.
6. Lower It Straight. Hold the strainer basket or dome by its rim with both hands. Align it with the drain opening and gently lower it straight down into the hole. The strainer should sit flush with the drain surface, with no visible gaps around the edge. If the fit is tight, rotate it gently back and forth until it settles. You should not force it—a basket strainer sits on its own weight and friction.
7. Test the Fit. Press down lightly on the center of the strainer basket and verify it doesn't wobble. It should be stable and level. Look around all four sides to confirm no gap exists between the strainer rim and the drain opening. If it's loose or rocks, remove it, wipe the rim again, and reinsert it. Most standard strainers need no adhesive or putty—friction and weight hold them in place.
8. Check Water Flow. Fill the sink or tub with water to about 2 inches depth. Let it drain while watching the strainer. Water should flow smoothly through the holes in the basket without pooling. If water backs up or drains very slowly, you likely have a clog below the strainer—remove the strainer and snake the pipe before reinstalling it. If water drains normally, the strainer is working.
9. Empty It Monthly. After 2–4 weeks of normal use, lift the strainer basket out of the drain and dump the collected hair and debris into the trash. Rinse the basket under running water to clear remaining buildup. Replace it in the drain immediately. This is not a one-time install—the strainer requires regular maintenance to function.
10. Replace When Cracked. After 12–24 months of use, basket strainers develop small cracks or the holes become deformed. If you see cracks, water will flow around it instead of through it, and hair will escape into the drain. Replace the old strainer with a new one using the same process. Replacement takes 2 minutes.