How to unclog a kitchen sink

Try three things in this order: plunge, open the trap, snake the line. Together they beat the large majority of kitchen clogs, and none costs more than a few dollars. Grease, rice, coffee grounds and scraps collect in the bend under the cabinet or a little way down the wall pipe. If all three fail, the line needs a plumber's machine, and our page on clogged toilets and drains explains that visit.

Where do I start when the sink will not drain?

Start with the plunger. Let about three inches of water sit in the basin, press a flat cup plunger over the drain, and pump hard roughly ten times before lifting. With a double sink, jam a wet rag into the other drain, otherwise the pressure escapes there. Water that drops away means you are done.

The detail that trips people up is the plunger shape. The toilet plunger with its extra lip will not seal on a flat sink, so use a plain cup. If you own a disposal, cut its power at the wall before plunging. Never put fingers into it. Plunging beats soft, nearby blockages. If the water barely moves, or surfaces in the neighbor bowl, move on to the pipe under the cabinet.

How do I open and empty the U-bend under the sink?

Park a bucket under the curved pipe, spin the two big slip nuts loose (pliers help if they resist) and let the U-shaped section drop out. Scrape out the sludge, rinse the piece, and refit it with its washers seated, nuts hand tight plus a final quarter turn.

Snap a photo before you start, so you can recall how the pieces align. In older parts of Santa Ana, around Floral Park for instance, the wall pipe behind the sink may be galvanized steel or cast iron, and rusty nuts can snap if forced, so ease off if anything refuses to turn. Once it is back together, let the tap run a minute and drag a dry fingertip around each joint; any damp spot means tighten again. A clean trap with a sink that still will not drain places the clog deeper in the wall.

What next if cleaning the trap changed nothing?

Reach for a hand snake. With the U-bend off, feed the cable into the pipe stub in the wall, cranking the handle as it goes, until it meets resistance, then work it back and forth to hook or crumble the blockage. Pull it out, wipe it, and run hot water through the line. A cable that will not advance may be hitting a broken pipe.

Basic hand augers are inexpensive and long enough for a typical branch line from a kitchen. Lay a towel over the cabinet floor and wear gloves; the cable comes out coated. If a disposal is fitted, enter by the trap arm and leave the disposal itself alone.

A sink that clogs again within a few weeks usually has grease caked along the wall of the pipe farther down. A plumber treats that with a camera and hydro jetting, which scours the full inside of the pipe instead of just punching a hole through it.

Is chemical drain cleaner ever a good idea?

Rarely. Liquid openers seldom cut through packed grease, they can harm plastic pipe, old metal and disposal seals, and the caustic liquid left standing in the pipe makes later plunging or snaking risky, because a splash can injure skin and eyes. Never combine one with any other cleaner, vinegar and baking soda included. Mechanical clearing is the safer path.

Already poured some in? Stop. Do not plunge or snake, put on eye protection and gloves, and let the plumber know which product it was. If the chemical touches skin or eyes or is swallowed, ring the Poison Help line at 1-800-222-1222. For gentler maintenance habits, see the clogged drain home remedy guide.

At what point should I hire a plumber?

Once the plunger, the trap and the snake have each failed, or two fixtures back up together, or a tub or floor drain fills while the sink empties, or the house smells of sewage, stop. Those signs mean something farther down the system is blocked, often by roots or a collapsed pipe.

The plumber arrives with a powered snake and a camera, adding hydro jetting when grease or roots are behind it. Price ranges live on the drain unclogging cost page, with sink figures in the sink clog pricing guide. Bathroom fixtures have their own page: a bathroom sink or a bathtub drain.

Ask for a written plumber quote

Tell us about the job. We'll arrange a visit and a written quote before any work starts.

Full name

Email

Mobile or phone

What is the job? Select one Plumber Water heaters Leaks and burst pipes Drain cleaning and clogs Toilets Repiping and pipe replacement Something else Not sure yet

Job address

Lets the business see where the job is before they quote.

City or town

When would you like it done? As soon as possible In the next two weeks In the next month or so Just getting prices for now

Job details (if you like)

I agree my details go to the local plumber business that will quote for this job, and that it may pay Santa Ana Plumbing Co for the introduction. Privacy policy

Send my details

What keeps the kitchen drain clear afterward?

Treat cooking fat as trash, not drain water: let it set in a can, bin it, and wipe pans with paper before they hit the sink. Fit a mesh strainer, and keep stringy or starchy food, like celery, potato peels and rice, out of the disposal. Once a month, flush the line with hot water and a little dish soap.

Air matters as well. A drain that gurgles while it empties is usually partly blocked, since air must follow water down the pipe. If more than one fixture gurgles, the trouble is probably farther along the line. The causes overlap with a slow bathroom sink, so that page is worth a look.

Common questions

How much time should I give the job?

Plunging is minutes, the U-bend is roughly half an hour, and snaking can reach an hour with cleanup. If you are still at it after an hour, phone a plumber. An ordinary clog takes a professional around an hour or two, more when a camera check or jetting comes into it.

Does hot water with dish soap work?

On a light grease film, sometimes. Use hot tap water, not boiling, which can stress plastic pipe and cracked fixtures. Squeeze in some dish soap, give it several minutes, then flush. Leave this alone if a chemical cleaner is already down there. It suits monthly upkeep better than a hard blockage.

Can one clogged sink affect the whole house?

If the blockage sits in a shared line, it can. A clog confined to one sink backs up only that sink. But a gurgling toilet while the sink empties, or water showing in a shower or floor drain, means the trouble is farther down the system. Stop running water and phone a plumber.

What does hydro jetting actually do?

A hose with a nozzle sends high-pressure water around the entire pipe wall, scouring off grease, scale and roots, while a snake merely bores a channel. A plumber decides whether your pipes suit it, since very old or damaged lines may not, and usually runs a camera first.