How to Unclog a Drain: A Drain Tech's Fixture-by-Fixture Guide

By Sal Marino · Published June 7, 2026 · 8 min read

How to unclog a drain: match the method to the fixture (plunger and trap for a sink, a hair tool for a tub, a closet auger for a toilet), and stop the second you see more than one fixture backing up, because that's a main-line job.

I've cleared drains for a living for fifteen years. Most of the calls I get could've been solved by the homeowner in ten minutes with a five-dollar tool, if somebody had just shown them the right move for that specific fixture. So here it is, fixture by fixture, no upsell.

The golden rule before you touch anything: a clog in one fixture is your problem to fix. A clog showing up in two or more fixtures at once is the main line, and that's where you stop and call a pro. I'll come back to that.

Bathroom Sink

Bathroom sinks clog from a paste of hair, toothpaste, and soap scum that builds up right in the P-trap, the U-shaped pipe under the sink. That's good news, because the P-trap is the easiest place in plumbing to reach.

Try these in order:

Plunge it. Fill the basin with a couple inches of water, block the overflow hole with a wet rag (this is the step everyone skips, and it's why plunging fails), and plunge hard a dozen times. The rag forces the pressure down the pipe instead of out the overflow.
Clean the P-trap. Put a bucket under the trap. Unscrew the two slip nuts by hand or with channel locks. Pull the trap, dump the gunk, scrub it out, reassemble. Nine times out of ten the clog is sitting right there.
Snake the wall pipe. If the trap was clean, the clog is deeper. Feed a hand drum auger into the pipe that goes into the wall and crank through it.

Most bathroom sinks never get past step two.

Tub and Shower

Tub and shower clogs are almost always hair, full stop. And there's a specific tool for hair that beats everything else.

Pop off the drain cover or stopper first. On many tubs the stopper unscrews or lifts out; on a trip-lever tub you may have to unscrew the overflow plate and pull the linkage. Then go in with a barbed hair tool. A Zip-It hair removal tool is a long plastic strip covered in backward barbs. Push it down, twist, and pull. The hair mat comes out in one disgusting rope. I've cleared tubs in under a minute this way that the homeowner had been dumping chemicals on for weeks.

Why not a flat plastic snake from the hardware store? Because flat tape has no barbs and no real grab. It pushes past hair or packs it tighter. The barbed tool is the right call here, and it costs about five dollars. If the hair tool comes up clean but the tub still drains slow, snake it with a hand auger, because soap scum can build deeper in the line.

Toilet

A clogged toilet has its own two tools, and a regular drain snake is not one of them. A bare cable will scratch and chip the bowl, and that's a new toilet.

Start with the right plunger. The flat cup plunger most people own is for sinks. Toilets need a flange plunger, the kind with a soft rubber sleeve that folds out of the cup to seal the bowl's trap-way. Get a good seal, then pump with real force. A toilet flange plunger clears most toilet clogs in under a minute when you've got a proper seal.

If plunging fails, reach for a closet auger, also called a toilet auger. It has a protective rubber boot so it won't mar the porcelain and a curved tube that aims the cable right into the trap. A Ridgid closet auger handles the toy, the wipe, or the wad of paper that a plunger can't budge. If the closet auger and the plunger both fail, the clog has moved past the toilet into the branch line, and that's a snake-the-line job.

One warning: never, ever pour caustic chemical drain cleaner into a clogged toilet. If it doesn't clear, you're now plunging a bowl full of corrosive water that can splash up at you. I've seen the burns.

Kitchen Sink (and the Grease Problem)

Kitchen sinks are the meanest residential clogs, because the enemy is grease. People pour cooking fat down the drain, it cools, congeals on the pipe wall, and over months it builds a hard layer that catches food scraps. Hot water and a plunger rarely beat a real grease clog.

Work it this way:

Plunge (overflow doesn't apply, but plunge the drain with water in the basin). If there's a dishwasher hose, clamp it first so you don't blow water into the dishwasher.
Clean the P-trap under the sink, same as the bathroom. Grease and food collect there.
Snake the line with a drum auger, ideally a drill-driven one for the extra torque grease needs. A drill-powered drum auger chews through grease far better than a hand crank.

Here's the honest part about grease: a snake punches a hole through the clog, but it doesn't scrape the grease off the pipe wall. So a snaked grease line tends to clog again. If your kitchen sink clogs every few months, the pipe wall is caked, and the real fix is to clean the whole pipe, which usually means hydro jetting versus snaking. And going forward, never pour grease down the drain. Wipe pans into the trash.

When to Stop and Call a Pro

This is the most important section, so read it twice. Put the tools down and pick up the phone when:

More than one fixture backs up at the same time. Flush the toilet and the tub gurgles or fills? Run the washer and the floor drain bubbles up? That's the main line, the big horizontal pipe to the street, not any single fixture. No hand tool you own reaches it. Keep going and you'll just make a mess. I walk through every warning sign in signs your sewer line is clogged.
The same drain clogs over and over. Recurring means buildup, a belly in the line, or roots. You're treating a symptom.
You see water coming up where it shouldn't, like at a basement floor drain or an outdoor cleanout. That's the main line overflowing.
You've snaked it twice and it won't clear. Stop before you damage the pipe or yourself.

A good drain tech with a camera and a power machine is cheaper than the water damage from a sewage backup. Curious what it runs? See my honest breakdown of drain cleaning cost, and if you want a vetted local tech, our pros directory lists folks who don't run the bait-and-switch.

A Few Habits That Prevent Most Clogs

I'd rather you never call me, honestly. Most of the clogs I clear were preventable with a couple of cheap habits. Here's what actually keeps drains flowing:

Catch hair before it goes down. A cheap mesh drain strainer in every tub and shower catches the hair that causes the majority of bathroom clogs. Empty it weekly. This one habit prevents more clogs than anything else.
Never pour grease down the kitchen drain. Cooking fat is liquid when hot and solid when cool, and it congeals on your pipe wall. Wipe pans into the trash or pour grease into a can. Hot water does not save you here; it just moves the grease farther down before it hardens.
Run plenty of water with the disposal. Food scraps need a strong flow to carry them past the trap. A trickle leaves them sitting.
Treat slow drains monthly with enzymes. A drain that's draining slow but not clogged is telling you the wall is coating up. Stay ahead of it.
Flush only the obvious in toilets. Toilet paper and waste, nothing else. "Flushable" wipes are not flushable; they're a leading cause of the clogs I cable out of branch lines.

None of this is glamorous, but a drain strainer and a no-grease rule will save you more service calls than any tool in your garage.

The Honest Take on Home Remedies and Chemicals

Two things every article tells you to try, and here's the truth from somebody who opens these pipes.

Baking soda and vinegar. It fizzes, it looks dramatic, and it does almost nothing to a real clog. The reaction is a weak, short-lived foam that can't break up a hair mat or a grease plug. It's fine as a mild freshener for a slightly smelly drain. It is not a clog remover. Don't waste an afternoon on it when a hair tool would've cleared the drain in 60 seconds.

Caustic chemical drain cleaners. I want to be straight with you: the lye and acid-based liquid drain cleaners are a stopgap at best and a hazard at worst. They generate heat that can soften PVC and warp it, they corrode older metal pipe and rubber seals, and when they don't fully clear a clog they leave a pipe full of dangerous liquid sitting against your fittings and waiting for whoever opens the trap next. For upkeep, an enzyme drain cleaner used monthly is the safe play. It digests the organic film slowly without eating your pipes. Mechanical first, enzymes for maintenance, caustic almost never.

Bottom Line

Most clogs are a one-fixture, ten-minute job if you use the right tool: a flange plunger and closet auger for the toilet, a barbed hair tool for the tub, a P-trap cleanout and a drum auger for the sinks. Skip the baking-soda theater and the caustic chemicals. And the moment you see two fixtures misbehaving at once, you've left DIY territory and entered main-line territory. Knowing that line is what keeps a $25 problem from turning into a flooded basement. Keep a cheap kit under the sink, use the right tool for the fixture, and call a pro when the signs say to.