Why Your Dishwasher Is Leaking From the Bottom (and How to Fix It)

A dishwasher leaking from the bottom can be a major inconvenience. Water on the floor can damage your floors and lead to mold growth. Fortunately, there are several potential causes of a leaky dishwasher and solutions to fix the problem.

Common Causes of Dishwasher Leaks

There are a few common culprits when a dishwasher leaks from the bottom:

Worn Door Seal

The door seal (also called a gasket) creates a tight seal between the door and the tub when the dishwasher is running. Over time, this seal can crack or tear, allowing water to leak out the bottom. Door seals are relatively inexpensive to replace and this repair often solves the leaking problem.

Clogged or Faulty Drain Line

Dishwashers drain through a tube that runs from the tub to the sink drain line. If this gets clogged with food debris, grease, or soap scum, water can back up and leak from the base of the dishwasher. Clearing the blockage is usually the fix, but a persistently clogging drain line may need to be replaced.

Rust Holes in the Tub

The metal tub inside your dishwasher can eventually rust and develop small holes, especially around weld points. As the tub fills with water, it leaks through these rust holes onto the floor. Your only option is to replace the entire tub.

Failed Water Inlet Valve

The inlet valve controls water flow into the dishwasher. If the valve fails, the dishwasher may overfill and leak water through vents in the tub bottom. Replacing the water inlet valve should stop this type of leak.

Faulty Pumps

Dishwasher pumps push water through the spray arms and drain the tub after the wash cycle finishes. A worn pump may leak slowly as the tub fills with water. Replacing the circulation or drain pump repairs this issue.

How to Diagnose the Cause of Leaks

Figuring out why your dishwasher is leaking is the first step to getting it fixed. Here are some tips for diagnosing the problem:

  • Inspect the door seal for cracks or tears and make sure it’s firmly in place around the door.
  • Check for a clog by disconnecting the drain line from the garbage disposal or sink trap. Run water through to see if it drains freely.
  • Look inside the tub for rust holes near seams and welds that could be leaking.
  • Remove the lower access panel and check for water on the floor pan under the dishwasher. Water here indicates a leak from the tub or internal components.
  • Run the dishwasher and watch closely to see where water is leaking from. Have a flashlight handy to illuminate the interior.
  • Listen for water running continuously, which may signal a stuck inlet valve.

Fixing a Leaky Dishwasher

Once you’ve diagnosed the problem, here are tips for some common repairs:

Replacing the Door Seal

  • Order the correct replacement gasket for your dishwasher make and model.
  • Pull the old seal off the door and clean the channel thoroughly.
  • Coat the new gasket lightly with dish soap and seat it evenly in the door channel, pressing firmly all the way around.

Clearing a Clogged Drain

  • Put a bucket under the drain tube to catch water.
  • Disconnect the drain line from the sink trap or garbage disposal.
  • Run water through the tube to flush out debris.
  • Reattach the drain line securely.

Replacing a Leaking Valve or Pump

  • Shut off electrical power to the dishwasher at the circuit breaker.
  • Detach water supply lines and drain tube.
  • Access internal components by removing the lower access panel.
  • Label wires to note connections, then disconnect and remove failed part.
  • Install new valve or pump, reconnect wires and hoses.

Preventing Future Leaks

To avoid recurring leaks:

  • Inspect and clean door seals regularly.
  • Periodically check and clean the drain line.
  • Use a dishwasher cleaner monthly to dissolve grease and limescale.
  • Don’t overload the dishwasher, which can lead to leaks.
  • Promptly replace the tub or internal parts at the first sign of leaks.

When to Call a Repair Professional

If you’re unsure of the cause of a leak or how to fix it, don’t hesitate to call a home appliance repair technician. A seasoned pro can accurately diagnose the problem and has the skills and tools to repair your dishwasher properly. Paying for an expert repair will often be less expensive than a new dishwasher.

FAQs About Dishwasher Leaks

What kind of damage can a leaky dishwasher cause?

Leaking dishwater can lead to warped or buckling floors, growth of mold and mildew, deterioration of cabinets and structural supports, and slippery surfaces that are a fall hazard. Electrical shorts are also possible if water contacts wiring.

Where do I locate the dishwasher door seal?

The seal attaches to the inner lip of the dishwasher door, forming a square or rectangular shape. When closed, the door presses the gasket against the tub opening to seal it.

Why does my dishwasher have a rust hole in the tub?

Hard water, food soils, detergent, and humidity eventually corrode the steel tub from the inside. Regular use of a dishwasher cleaner can help prevent tub corrosion.

How can I unclog a stopped-up dishwasher drain?

Try using a zip-it cleaning tool, plumber’s snake, or bending a wire coat hanger to hook and dislodge clogs. Avoid chemical drain cleaners, as they can damage the drain line and dishwasher parts.

When should I replace a leaking water inlet valve?

If shutting off power stops the leak, the inlet valve is most likely faulty and should be replaced. This valve controls water flow into the dishwasher.

Is it worth paying for dishwasher repairs?

For minor leaks from a door seal or drain issue, repairs are often inexpensive and worthwhile. But for major tub, pump, or control panel leaks, replacement may be a better investment.


A leaking dishwasher, while frustrating, usually has a limited number of causes. Inspecting door seals and plumbing connections, clearing drain clogs, and replacing worn parts can typically solve the problem. For major leaks or unknown causes, rely on appliance repair experts to properly diagnose and fix your dishwasher. With prompt attention, your dishwasher can be back washing dishes leak-free.