Dishwasher Not Draining? How to Clear It Yourself
Standing water in the bottom of the dishwasher is almost always a clog you can clear yourself. Here's how to find it — filter, drain hose, or air gap — and fix it.
Opening the dishwasher to a pool of dirty water in the bottom is unsettling, but it's rarely a broken machine. Standing water means the dishwasher isn't draining, and that almost always comes down to a clog somewhere along a short, accessible path. Most fixes take under an hour and cost nothing.
Safety first. Before reaching into the tub, turn the dishwasher off at the breaker (or unplug it). You'll be working near the drain and pump.
First, bail out the water
Scoop the standing water with a cup, then sponge or towel out the rest so you can see and reach the bottom of the tub. (Tip: lay towels under the door — there's always more water than it looks.)
1. Clean the filter (the usual culprit)
Modern dishwashers have a removable filter in the floor of the tub, usually a cylinder you twist out plus a flat screen underneath. This is where food, grease, and debris collect — and the #1 reason for poor draining.
- Twist and lift out the filter assembly.
- Rinse it under the faucet, scrubbing with a soft brush; soak in warm soapy water if it's greasy.
- Wipe out the screen area and reseat it firmly.
This is the same part behind the clean the dishwasher filter maintenance task — doing it every few months prevents most drainage problems (and the smell). For a full refresh, see how to clean a dishwasher.
2. Clear the sump and drain opening
With the filter out, look into the sump below it — the low point where the drain and pump sit. Broken glass, fruit labels, twist ties, and chunks of food love to lodge here and block the drain. Clear anything you find by hand (carefully) and check that the drain opening is clear.
3. Check the drain hose and disposal
The dishwasher drains through a hose that usually ties into the garbage disposal or sink drain. Under the sink:
- Make sure the drain hose isn't kinked or crushed behind the cabinet.
- Check the disposal connection for a clog, and run the disposal to clear the sink side — a backed-up disposal stops the dishwasher from draining.
- New install? A classic cause: the knockout plug inside the disposal's dishwasher inlet was never removed, completely blocking the line.
4. Clean the air gap
If you have a small chrome cylinder on the counter behind the faucet, that's the air gap that prevents drain water from siphoning back. Twist off the cap, pull the cover, and clear any gunk inside — a clogged air gap shows up as water backing up or spitting out of it.
When to call for service
If the filter, sump, hose, disposal, and air gap are all clear and it still won't drain, the drain pump itself may have failed or be jammed by a foreign object — you may hear it hum without moving water. That's the point to call an appliance tech, especially weighed against the machine's age and the repair-or-replace math.
Why it's worth staying ahead of
A dishwasher that drains poorly leaves residue on dishes, smells musty, and shortens the pump's life. A clean filter and a quick monthly look are all it takes to avoid the standing-water surprise. For the full routine, see the appliances system overview.
Make it automatic
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