What To Do If a Dishwasher Won’t Drain

Next steps (at a glance)

If you only do 3 things:

  1. Stop running the dishwasher and avoid forcing another cycle.

  2. Check for simple blockages you can safely see.

  3. If standing water keeps returning, schedule service.

Urgency level: Low → Medium
(Becomes High if water backs up into the sink, leaks onto the floor, or you smell burning or electrical odors.)

Short answer

A dishwasher that won’t drain is usually caused by a blocked filter, clogged drain hose, air gap issue, or garbage disposal connection problem. Many causes are simple; repeated standing water usually isn’t.

Running the dishwasher repeatedly without drainage can damage the pump and seals.

Why dishwashers stop draining

Dishwashers rely on a pump to move water out through a drain path. Any restriction along that path can stop drainage.

Common trouble spots include:

  • Internal filters

  • Drain hose bends or clogs

  • Air gaps (where present)

  • Garbage disposal inlet plugs

Common causes of a dishwasher not draining

  • Food debris clogging the filter

  • Kinked or clogged drain hose

  • Blocked air gap (small cylinder near sink)

  • Garbage disposal plug not removed (new installs)

  • Failing drain pump

Most drainage issues start small and worsen if ignored.

What happens if you keep using it anyway

  • Standing water damages seals and components

  • Food debris hardens inside the unit

  • Mold and odors develop

  • Pump strain increases repair cost

Dishwashers aren’t designed to sit with water inside.

Typical dishwasher lifespan context

  • Dishwashers: often 9–12 years
    Early failure clues: repeated drainage issues, leaks, loud pump noises

  • Drain pumps: variable lifespan
    Early failure clues: humming without draining, inconsistent performance

Repeated drainage problems can shorten appliance life.

Warning signs to take seriously

  • Standing water after every cycle

  • Gurgling sounds in nearby sinks

  • Water backing up when the dishwasher drains

  • Leaks under or around the unit

  • Burning smells or electrical odors

Leaks or odors increase urgency.

DIY-safe checks you can do

These checks are generally safe for homeowners:

  • Remove and clean the dishwasher filter

  • Check for visible debris at the drain opening

  • Inspect the drain hose for obvious kinks (without disconnecting)

  • If present, clean the air gap cap

Do not disassemble the dishwasher or access wiring.

Maintenance that actually helps

  • Clean the filter regularly to prevent buildup

  • Rinse heavy food debris before loading

  • Run hot water at the sink before starting cycles

  • Pay attention to new noises during draining

Basic care reduces repeat clogs.

If you don’t want to call a professional yet but want to stay safe

Prioritize these:

  • Stop rerunning cycles with standing water

  • Clear filters and visible debris once

  • Monitor whether water returns immediately

If water still won’t drain after basic checks, professional service is the safest next step.

Common mistakes

  • Repeatedly restarting cycles

  • Using chemical drain cleaners

  • Ignoring standing water between uses

  • Forcing parts open or removed

Dishwashers are sealed systems—forcing fixes often causes leaks.

When to call a professional

Contact an appliance technician if:

  • Water remains after filter cleaning

  • Drain pump sounds abnormal

  • Leaks appear beneath the unit

  • Electrical odors are present

What to ask:

  • Whether the issue is blockage or pump-related

  • Repair versus replacement considerations

What to expect:
Costs vary by cause. Early service usually costs less than pump or control board replacement.

Related guides

Disclaimer:
This is general information only. When in doubt, hire a licensed professional.