Dishwasher not draining: clear the standing water and check the filter, hose, air gap, disposal and pump in order

How much water in the bottom is normal

Many dishwashers keep a small amount of clean water in the sump, the well under the filter. One manufacturer's support guide describes 1 to 2 cups of clean water covering the bottom of the tub as normal on its models without an ultra-fine filter. Dirty water, food in the water or water above the filter after a full cycle is a problem.

Before you take anything apart:

1. 01

   Check the cycle finished

   A door opened mid-cycle, a power cut or a child lock can stop a cycle before the final drain.

2. 02

   Run a drain or rinse cycle

   Many models have a cancel-and-drain option; check the manual for the button sequence.

3. 03

   Look for an error code

   Note any code on the display. The manual explains it, and it is useful for a technician.

How to remove standing water from a dishwasher

1. 01

   Power off

   Unplug the dishwasher or switch off its breaker.

2. 02

   Protect the floor

   Lay old towels in front of the door and have a bowl and a bucket ready.

3. 03

   Take out the lower rack

   This gives you room to work.

4. 04

   Bail out

   Scoop water into the bucket with a cup, then soak up the rest with a sponge or towels.

5. 05

   Wear gloves

   Feel carefully: broken glass, bones and fruit pits end up in the sump.

Dishwasher not draining: the checks, from easiest to hardest

1. Clean the filter

Most modern dishwashers have a manual filter: a cylinder and a flat mesh at the bottom of the tub, usually under the lower spray arm. University of Illinois Extension advises cleaning the filter at the bottom of the dishwasher of food, debris and glass.

1. 01

   Unlock the filter

   Twist the cylinder counterclockwise and lift it out, then lift the flat mesh underneath. The manual shows the exact steps for your model.

2. 02

   Rinse under warm running water

   Use a soft brush on the mesh. Hard objects can damage the mesh, so pick them out by hand.

3. 03

   Look into the sump

   With a flashlight, check the opening below for labels, bones, pits and glass.

4. 04

   Refit it properly

   Seat the mesh flat and lock the cylinder fully. A filter left loose lets debris reach the pump.

2. Check under the filter

On many models a small cover over the drain pump sits below the filter. If your manual shows how to remove it, take it off and check that the impeller (a small plastic wheel) turns freely, removing any glass or pits with gloves or tongs. If your manual says the pump is service-only, skip this step.

3. Check the drain hose

The drain hose runs from the back of the dishwasher to the sink drain or the disposal. Look under the sink first, then pull the dishwasher out gently (power off, and watch the water supply line) to see the hose behind it.

• Kinked or crushed hoses are common after the dishwasher has been pushed back into place.
• Clogged hoses: disconnect the sink end over a bowl and check for a plug of food or grease.
• Old, stiff hoses are worth replacing; a manufacturer guide suggests the corrugated hose supplied with new dishwashers.

4. Check the high loop or air gap

Dishwasher drains need protection so dirty sink water cannot flow back into the tub. There are two ways to do it:

• High loop: the drain hose rises as high as possible under the counter before it drops to the drain, usually fastened up under the countertop. The manufacturer guide quoted above says a high drain loop is required when there is no air gap and gives the height in the installation instructions.
• Air gap: a small chrome or plastic cap on the sink or countertop. Water runs up to it and falls through open air to the drain. If water spurts out of the cap, take the cap off and clear out the debris.

Which one is required depends on your local plumbing code. In Saint Paul, Minnesota, for example, a replacement dishwasher can be installed without a plumbing permit only when the discharge line is raised to the highest possible point or runs through a code-compliant air gap, while a new dishwasher installation needs a permit. Ask your building department what applies where you live.

5. Check the garbage disposal

Most dishwashers drain into the side of the garbage disposal (waste disposal unit, in British English).

• Run the disposal first with cold water, so food in it is not blocking the dishwasher inlet.
• New disposal? Disposals come with a knockout plug sealing the dishwasher inlet. If it is still there, the dishwasher cannot drain at all. With the power off, remove it as the disposal's instructions show, and take the loose piece out of the disposal. Our garbage disposal guide covers the details and other disposal faults.
• Jammed or humming disposal: fix that first, as the same guide explains.

6. Check the sink drain

The dishwasher shares the trap and drain with the kitchen sink. If the sink is slow, the dishwasher has nowhere to send its water. Clear the sink first: see how to unblock a sink. If several drains in the house are slow at once, the problem is further down the line: see sewer cleanout.

7. Run a test cycle

Reassemble everything, turn the power back on and run a short rinse or drain cycle. Listen: you should hear the pump start and the water leave within a few minutes. Check under the sink for drips at every connection you touched.

Signs of a drain pump problem

• Humming or buzzing at the drain stage, with no water moving: a jammed impeller or a seized motor.
• Silence at the drain stage: a failed pump, wiring or control fault.
• A drain error code that returns after the filter, hose and drain are clear.
• Grinding noises: glass or a pit caught in the pump.

Clearing a jam under the filter, where the manual allows it, is fine. Replacing the pump means opening the base of the machine and working near wiring, so most people leave it to a technician.

How to keep a dishwasher draining

• Scrape plates into the trash before loading; bones, pits, labels and toothpicks are classic pump jammers.
• Clean the filter regularly, more often if you load heavily soiled dishes.
• Run the disposal before starting the dishwasher.
• Keep grease out of the sink drain: it lines the shared trap.
• Freshen it up if it smells: University of Illinois Extension suggests 2 cups of white vinegar in an upright glass container on the lower rack, run on a normal cycle with heated dry (no detergent), then 1 cup of baking soda sprinkled in the tub and a hot cycle. Follow your manufacturer's instructions if they differ.

When to call a technician

• The dishwasher hums, buzzes or stays silent at the drain stage after you have cleaned the filter.
• An error code returns after every check.
• Water leaks onto the floor from under the machine.
• You smell burning, or the breaker trips.
• It is a portable dishwasher connected to the faucet: one manufacturer notes these may need service when they will not drain.

Tell the technician the model number, any error code, what you have already checked and whether a disposal or sink work was done recently.

Sources

Official and manufacturer guidance, checked on 27 October 2026.

• GE Appliances · Dishwasher not draining ↗Normal water in the tub, drain hose kinks and replacement, the high drain loop, clearing the air gap, running the disposer and removing its drain plug, portable models.
• University of Illinois Extension · Cleaning and sanitizing ↗Cleaning the filter of food, debris and glass, and the vinegar and baking soda cycle.
• City of Saint Paul, Minnesota · Dishwasher appliance installation policy ↗Permits for new installations and the elevated discharge line or code-compliant air gap.
• CDC · Protect yourself from electrical hazards ↗Switching off at the breaker, staying out of standing water and having wet electrical equipment checked by an electrician.