How do I unclog a kitchen sink without chemicals?

You can clear most kitchen sink clogs with a plunger and a bucket. Plunge first, with the second opening sealed. If that fails, open the U-shaped trap under the sink and clean it out. Most clogs are in the trap^[1], usually a plug of grease and food scraps. A hand snake handles what sits further along. None of it needs a chemical opener.

Check the disposal first

If your sink has a garbage disposal, find out whether the disposal or the drain is the problem. With water standing in the sink, switch the disposal on. If the disposal runs and you see a whirlpool in the water, the clog may be in the drain line, not the disposal.^[2] If it runs but no whirlpool forms, or it will not start at all, the disposal itself needs attention, covered in what not to put down a garbage disposal. Do not stick your hand in the disposal.^[2]

Plunge it properly

A plunger works by pushing a slug of water against the clog, so it needs a sealed system and enough water to push.

• Seal the second opening. In a double bowl sink, plug the other drain; in a single bowl, plug the overflow opening with a washcloth or rag, and keep the plug in place.^[1] Otherwise the push comes straight back up the other side.
• Use enough water. InSinkErator's instructions call for about four inches of water in the sink^[2], enough to cover the plunger's cup.
• Use the right plunger. A flat-rimmed cup plunger seals best on a flat sink bottom. The flanged kind made for toilets often rocks and leaks air on a sink.
• Work it hard. Set the cup over the drain, press the plunger down smoothly, jerk it up sharply, and repeat 20 to 30 times.^[1] The pull matters as much as the push.

If that clears it, rinse the drain with hot soapy water.^[1] If the water level does not move at all, repeat once before moving on.

If a dishwasher drains through the sink plumbing, a hard push can send dirty water back up its hose into the dishwasher. Run the dishwasher's drain cycle afterwards and check it is clean.

Clean the trap

When plunging fails, go to the trap: the U-shaped bend of pipe directly under the drain. Bail as much water out of the sink as you can first, because everything in the sink will come out of the trap.

If the trap has a cleanout plug, set a pan or bucket under it and unscrew the plug with an adjustable wrench.^[1] Most modern plastic traps have no plug; instead, two large slip nuts hold the trap in place, and they usually loosen by hand. Lower the trap into the bucket.

Use your finger, a pencil or a piece of wire to pull the clog out of the trap^[1], wearing gloves. Look into the short arm of pipe that runs into the wall as well, since grease often collects there. Put the trap back with its washers seated, tighten the nuts by hand until snug, and run hot soapy water while you watch the joints. A slow drip usually means a washer is out of place, not that the nut needs forcing; plastic threads crack when overtightened.

Then a hand snake

The EPA's alternative to chemical drain cleaner is a plunger or a plumber's snake.^[4] If the trap was clear, the clog is in the pipe in the wall. With the trap off, feed a hand snake (a drum auger) straight into that pipe, turning the handle as you push. When it stops, keep turning and push gently; when it gives, run it a little further, then draw it back slowly and clean what it brings up. Reattach the trap and test with hot water.

Stop if the snake jams hard and will not turn. Older galvanized or cast-iron pipe inside a wall is not worth forcing a cable through.

What to skip

Chemical openers. Chemical drain cleaners help only with sluggish drains, are caustic, and can burn you or damage pipes or fixture finishes.^[1] If you do use one, read the label, never add a second brand or type on top of one that did not work, because the mix can give off deadly fumes, and do not plunge a drain with chemical in it.^[1] Their poisonous ingredients include lye (sodium hydroxide or caustic soda) and hydrochloric acid.^[6] On a septic system, the EPA says to avoid chemical drain openers and use boiling water or a drain snake instead.^[5] InSinkErator lists caustic drain cleaners among the things not to put into a disposal.^[3]

Hot water as a fix for grease. Hot water moves grease along but does not get rid of it. As King George County's service authority explains: "When mixed in small amounts with hot water, F.O.G. flows easily. But once it cools, it hardens inside pipes."^[7] That is why a grease clog that clears with hot water tends to come back.

Baking soda and vinegar. The fizz looks busy, but it has little force. It is not a substitute for a plunger on a sink that will not drain.

Stop and call a pro if

• Water comes up in another fixture while the sink drains, or several drains are slow at once. Fairfax County's wastewater division puts it this way: "If the backup occurs only when facilities (such as toilet, tub, washer or sinks) are used, it is possible that you need a plumber."^[8]
• A chemical opener is already in the drain. Do not plunge it or open the trap; tell the plumber which product you used.
• The snake stops hard in the wall, or the trap and wall pipe are old metal that will not come apart.
• The trap leaks after you put it back and new washers do not fix it.
• The sink clogs again within weeks. The blockage is likely further down the line than a hand snake reaches.

For more help, see when a clog needs a plumber instead of a plunger, how to keep a kitchen sink from clogging and what a plumber charges to unclog a drain in Virginia. You can also browse plumbing repair answers or look up plumbers in Blacksburg.

Still stuck? Describe the clogged sink once and licensed local plumbers quote it.