Dishwasher Not Draining? Here's Exactly How to Fix It
Dishwasher not draining? Fix standing water in your dishwasher with our step-by-step guide. Covers all brands — Bosch, Samsung, Whirlpool, GE, LG & more.
Updated April 6, 2026 · 8 min read
Key Takeaway: Dishwasher not draining? Fix standing water in your dishwasher with our step-by-step guide. Covers all brands — Bosch, Samsung, Whirlpool, GE, LG & more.
Why Won't Your Dishwasher Drain?
Finding standing water at the bottom of your dishwasher after a cycle is one of the most common appliance problems homeowners face. The good news is that the cause is usually something simple — a clogged filter, a kinked hose, or a blocked garbage disposal — and you can fix most drainage issues yourself in under 30 minutes.
Cause 1: Clogged Drain Filter (Most Common)
This is the #1 cause of dishwasher drainage problems across every brand. The drain filter sits at the bottom of your dishwasher tub and catches food particles to prevent them from clogging the drain pump. When it gets packed with debris, water can't pass through.
How to clean it: Remove the bottom rack. Locate the filter assembly at the bottom center — it's usually a cylindrical mesh filter that twists out counterclockwise. Pull it out and rinse it under hot running water. Use an old toothbrush to scrub away grease and stuck-on food. Reassemble and test.
How often to clean: Clean your dishwasher filter once a month to prevent future clogs. If you pre-rinse dishes, you can stretch this to every 2–3 months.
Cause 2: Garbage Disposal Knockout Plug
If your dishwasher was recently installed or you got a new garbage disposal, this is an extremely common oversight. Garbage disposals come with a knockout plug inside the dishwasher drain inlet. This plug must be removed if you connect a dishwasher drain hose to the disposal.
How to check: Disconnect the dishwasher drain hose from the disposal inlet. Look inside the inlet — if you see a solid plastic disc blocking the opening, that's the knockout plug. Use a screwdriver and hammer to punch it inward, then reach into the disposal and remove the loose plug.
This fix takes 2 minutes and solves the problem completely.
Cause 3: Kinked or Clogged Drain Hose
The drain hose runs from your dishwasher to either your garbage disposal or the sink drain. If this hose is kinked, pinched, or clogged, water backs up into the dishwasher.
How to inspect: Pull the dishwasher out from under the counter (unplug it first or turn off the breaker). Trace the drain hose from the dishwasher to where it connects under the sink. Look for any sharp bends, kinks, or pinch points — especially where the hose passes through the cabinet wall. Straighten any kinks.
If the hose is clogged: Disconnect both ends and blow through it or run water through it. If water won't pass, replace the hose. A universal dishwasher drain hose costs $8–$15.
Cause 4: Clogged or Faulty Drain Pump
Every dishwasher has a drain pump that actively pushes water out through the drain hose. If the pump is clogged with glass, food debris, or a piece of broken dish, it won't move water.
How to check: With the filter removed, look into the sump (the lowest point at the bottom of the tub). You may see the drain pump impeller — check for any debris blocking it. Remove any visible obstructions with tweezers.
Signs of a failed pump: If the pump motor doesn't hum at all during the drain cycle, it may have burned out. Replacement drain pumps cost $30–$80 depending on brand and model.
Cause 5: Sink Drain or Air Gap Blockage
Your dishwasher drain connects to your home's plumbing — usually through the garbage disposal or a dedicated drain port under the sink. If the sink drain itself is slow or clogged, your dishwasher can't drain either.
Quick test: Run the kitchen sink and see if it drains normally. If it's slow, clear the sink drain first — that may fix the dishwasher too.
Air gap issues: Some installations include an air gap — a small cylinder mounted on the countertop or sink. If water sprays out of the air gap during the dishwasher drain cycle, remove the cap and clean out any debris inside.
Cause 6: Drain Hose Not Looped High Enough
The dishwasher drain hose must create a high loop — going up to the underside of the countertop before going back down to the disposal or drain. Without this loop, dirty water from the sink can siphon back into the dishwasher.
If there's no high loop and no air gap, water may also not drain properly because there's no break in the siphon. Secure the hose to the underside of the counter with a hose clamp or zip tie at the highest point possible.
When to Call a Professional
If you've cleaned the filter, checked the drain hose, confirmed the disposal knockout plug is removed, and the drain pump sounds like it's running — but water still won't drain — you likely need a professional. The issue could be a failed drain pump motor, a faulty control board not sending the drain signal, or a check valve stuck closed.
Professional dishwasher drain repair typically costs $100–$200 for the service call plus parts. Most repairs are completed in a single visit.
Still have standing water in your dishwasher? Our expert technicians can diagnose and fix it today. Same-day service available. Schedule a Repair →
Related Repair Guides
How Hard Water Accelerates Drain Problems in South Florida Dishwashers
Hard water creates mineral scale on internal dishwasher components faster than most homeowners realize. The drain filter, check valve, and pump impeller are the three components most affected by mineral accumulation. In South Florida's very hard water environment, filter clogs that would take six months to develop in a soft-water city can form in eight to twelve weeks in a dishwasher used daily. Calcium deposits inside the drain hose narrow the effective diameter over time, reducing flow even when the hose appears kink-free and the pump is functioning correctly. Running a citric acid dishwasher cleaner every 60 to 90 days in South Florida homes, combined with monthly filter cleaning, typically reduces drain repair calls to near zero for machines under eight years old.
When Standing Water Becomes a Health Concern
Standing water at the bottom of a dishwasher after a cycle is a growing environment for bacteria and mold if left unaddressed. The warm, humid interior of a dishwasher with standing water can develop microbial growth within 24 to 48 hours, especially during South Florida summers when ambient temperatures keep the interior of appliances warm even when not running. If you notice standing water, run a manual drain cycle immediately if the option exists on your control panel, or use a sponge or turkey baster to remove as much water as possible before leaving the dishwasher sitting. Leave the door slightly ajar to allow moisture to evaporate. Do not run another full wash cycle before addressing the drain issue.
Drain Pump Failure vs Control Board Failure: How to Tell the Difference
A failed drain pump produces a specific symptom pattern: the machine finishes the wash cycle, the control board sends a drain command, you hear nothing, and water stays in the tub. The pump is electrically dead or mechanically jammed. A control board failure produces a different pattern: the machine may stop partway through a cycle, the drain cycle may skip entirely, or error codes may appear alongside the drainage complaint. The distinction matters because drain pump replacement is a mechanical repair costing $150 to $230, while control board diagnosis and replacement can run $210 to $320 and requires confirmation that the board is actually the cause. Sharing this symptom detail — does the pump run and fail to drain, or does the pump never activate at all — helps your service dispatcher route the correct technician.