Wondering what's going on in there?
How a kitchen sink drains, in plain English
Water leaves the sink, passes through the disposal if you have one, dips through a U-shaped pipe, and runs into the wall. From there it joins the main drain the whole house shares. A clog can sit at any of those spots.
- The sink drains. On a double sink, the two sides join under the counter. Block one side when you plunge the other.
- The disposal. If it's jammed, water can't get past it.
- The U-shaped pipe (trap). It holds a little water to keep sewer smells out. Grease and food pile up here.
- The wall pipe. Grease can coat it farther in. A hand snake reaches it.
- The main drain. The one big pipe every drain shares. When it clogs, several drains slow down.
So a clogged kitchen sink usually means one of these:
- A jammed disposal.
- Food and grease in the U-shaped pipe, which a plunger or cleaning clears.
- Grease farther into the wall, which a snake clears.
- A main drain clog, if other drains are slow too.
Both sides clogged? The clog is usually past where the two sides join, so plunging one side won't reach it. Disposal won't run? See our guide to a garbage disposal that's not working. Dishwasher full of water too? It drains into the same pipe. See a dishwasher that's not draining.
Bathroom sink slow? See our bathroom sink guide. Water dripping under the sink instead? See our garbage disposal leaking guide.
Rather not do it yourself? Call a plumber.
That's a fine choice. Maybe you're busy. Maybe you're selling the house and just want it done right. A plumber can clear a clog that won't budge and check the pipe in the wall.
Most plumbers charge $45–$200 an hour, and some add a fee to come out. A camera look or water jetting costs more.
Find plumbers near you
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What to say
Calling a pro? Here's what to say.
A few lines to read when they pick up, and the questions to ask before anyone comes out.
Before you call
Say this
Hi. My kitchen sink is clogged. When's the soonest you can get here? And what's your fee for the visit? Does it go toward the repair?
Always ask
- What's your fee to come out, and does it go toward the repair?
- Do you charge by the job or by the hour?
- Will you tell me the full price before you start any work?
Watch out if
- They push a full replacement on the first visit for a small problem.
- They won't give you a price before starting.
- They add an emergency fee without telling you first.
Feeling pushed to decide on the spot? You can say no and hang up. You owe nothing for a phone call.
Answer up to 5 quick questions. We'll give you the words a pro uses.
Answer the questions →More of a list person?
Common sink clogs, causes, tests and costs
Find the row that sounds like your sink. The quick test is something you can check yourself in a few minutes.
| What you notice | What it probably is | Quick test | Do it yourself | With a pro | Verdict |
|---|---|---|---|---|---|
| Water comes up in other drains; sewage smell | The main drain is backing up | Run the sink and watch the tub or floor drain | Pro job | $100–$800 | CALLSee the answer: The main drain is backing up |
| Several drains slow; toilet gurgles | The main drain is slowing down | Run a bathroom sink and flush the toilet | Pro job | $100–$800 | CALLSee the answer: The main drain is slowing down |
| Drain cleaner used; water still standing | Drain cleaner is sitting in the pipe | None. Leave it alone | Pro job | $100–$275 | CALLSee the answer: Drain cleaner is sitting in the pipe |
| Sink full; disposal hums, clicks or won't run | The disposal is jammed or switched off | Flip the disposal switch on for a second | Free | Not needed | FIXSee the answer: The disposal is jammed or switched off |
| Standing water; a plunger clears it | A clog in the curve of the pipe, cleared | Use a cup plunger | Free | Not needed | FIXSee the answer: A clog in the curve of the pipe, cleared |
| Plunger didn't work; trap full of gunk | The U-shaped pipe was clogged, and you cleaned it out | Take the U-shaped pipe off and look | Free | Not needed | FIXSee the answer: The U-shaped pipe was clogged, and you cleaned it out |
| Trap was clear; a hand snake clears it | The clog was in the pipe inside the wall | Snake the pipe that goes into the wall | Free | Not needed | FIXSee the answer: The clog was in the pipe inside the wall |
| Plunger, trap and hand snake didn't help | The clog is too deep for hand tools | None. Call a plumber | Pro job | $100–$275 | CALLSee the answer: The clog is too deep for hand tools |
2026 U.S. averages, rounded. Pro prices include parts and labor. Most plumbers charge $45–$200 an hour, and some add a fee to come out. Nights, weekends and big cities cost more. See all repair prices
Want proof it's just the kitchen?
The other-drains test
This one test tells you whether the problem is the kitchen sink or the main pipe for the whole house.
- Run a bathroom sink for a minute.
- Flush a toilet once.
- Watch the tub drain and any basement floor drain while you do.
- Everything else drains fine: the clog is in the kitchen's own pipes. Start with the disposal and a plunger.
- Other drains are slow, the toilet gurgles, or water comes up: it's the main drain. Stop using water and call a plumber.
Not sure it's safe to keep going?
Stop and call a plumber if…
- You poured in drain cleaner and the water's still standing. Don't plunge, open the pipe, or run the disposal. Drano says the same.
- Water comes up in a tub, shower or floor drain.
- It smells like sewage, or several drains are slow at once.
- The pipes under the sink are cracked, rusty, or leaking.
Skip boiling water. Home Depot and Angi both warn it can damage plastic pipes. Hot tap water is fine.
Got a big plumber's quote?
Is the price fair?
Most kitchen clogs cost nothing to clear yourself. When you need a plumber, HomeAdvisor lists $110–$215 for a kitchen sink, and HomeGuide lists $100–$275 for a simple sink clog. Ask yourself three things:
- Is it just the kitchen? One sink should be a snaking job. A main line clog runs about $100–$800.
- Do they want a camera look? It makes sense when a line keeps clogging, not for a first kitchen clog.
- Is grease the cause? Ask what they found, so you can keep it from coming back.
Example: $175 to snake a kitchen drain is fair. $700 for a first-time kitchen clog is worth a second quote.
Ran into a word you don't know?
Drain words, explained
Tap through these before you open the cabinet. The drawings show roughly what each part looks like.
- Trap (P-trap)
- The U-shaped pipe under the sink. It holds a little water to keep sewer smells out.
- Slip nuts
- The big plastic or metal nuts on each end of the trap. They unscrew by hand or with pliers.
- Wall pipe (branch drain)
- The pipe that runs from the trap into the wall and on to the main drain.
- Cup plunger
- A plunger with a flat rubber cup, for sinks, tubs and showers.
- Double sink
- A sink with two sides. Their drains join under the counter.
- Garbage disposal
- The grinder under the sink drain. It has a red reset button and a hex hole on the bottom.
- Hex wrench
- A small L-shaped wrench that fits the hole in the bottom of a disposal to free it.
- Dishwasher drain hose
- The hose that carries dishwasher water to the sink drain or disposal.
- Hand snake (drain auger)
- A coiled metal cable you crank down a drain to break up or pull out a clog.
- Main drain (sewer line)
- The one big pipe that carries water from every drain out of the house.
- Drain cleaner
- A strong chemical sold to clear clogs. Read the label. Never plunge after using one if the drain is still clogged.
Still have questions?
Questions people ask most
Why are both sides of my kitchen sink clogged?
When both sides of a kitchen sink are clogged, the clog is past the point where they join under the counter. Plunge one side while someone blocks the other, then clean the U-shaped pipe.
Is a clogged kitchen sink an emergency?
A clogged kitchen sink is usually not an emergency, but water coming up in a tub, shower or floor drain is. That means the main drain is backing up, so stop using water and call a plumber today. Also call if you poured in drain cleaner and the sink is still full; don't plunge it or run the disposal.
How do I unclog a kitchen sink with a garbage disposal?
To unclog a kitchen sink with a garbage disposal, first make sure the disposal runs. Press its reset button and free it with the hex wrench. Then plunge with the disposal off. Don't run it if drain cleaner is still in the sink.
I've tried everything. What now?
If a plunger, cleaning the U-shaped pipe and a hand snake didn't work, the clog is deep and it's time to call a plumber. HomeAdvisor lists $110–$215 for a kitchen sink.
Will boiling water unclog a kitchen sink?
Boiling water isn't a good way to unclog a kitchen sink: Home Depot and Angi both warn it can damage plastic pipes. Use hot tap water instead. For grease, Angi suggests dish soap and hot water.
Does baking soda and vinegar work?
Baking soda and vinegar can help with small clogs, Home Depot and Angi say. It won't hurt your pipes, but it rarely clears a full clog. A plunger is faster.
Can I use drain cleaner in a kitchen sink?
Drain cleaner isn't the best choice for a kitchen sink; a plunger and cleaning the U-shaped pipe are safer. If you do use it, follow the label exactly. Drano says never to plunge during or after use, and not to run the disposal if the drain didn't clear.
How do I keep my kitchen sink from clogging?
To keep a kitchen sink from clogging, never pour grease, fats or oils down the drain. Scrape plates into the trash. Angi also says not to grind more than about a cup of food waste at once.
Who do I call for a clogged kitchen sink?
Call a plumber or a drain cleaning company for a kitchen sink clog you can't clear. If the disposal is the problem, a plumber can fix or replace it too. Several slow drains at once mean the main drain, which is a plumber's job.
How we built this
The questions follow the order a plumber checks a clogged kitchen sink: other drains, the disposal and any drain cleaner, then a plunger, the U-shaped pipe, and a snake into the wall. Each answer makes some causes more likely and others less likely.
Prices are 2026 national averages from published repair-cost guides, rounded. Your local prices will differ.
- HomeAdvisor, cost to unclog a drain (June 2026)
- HomeGuide, drain cleaning cost (December 2025)
- Angi, how to unclog a kitchen sink (July 2026)
- The Home Depot, how to unclog a kitchen sink (May 2025)
- Drano, Max Gel Clog Remover directions and warnings (read October 2026)
How we make money: some links go to parts stores that pay us a small commission, and some pro listings pay us when you call them. Verdicts come from the diagnosis, not from who pays more.