Bosch Dishwasher Not Draining — How to Fix It

What Does This Error Mean?

Bosch dishwashers fail to drain in most cases because the filter at the bottom of the tub is blocked — clean it first before anything else. Twist out the cylindrical filter, rinse it under running water, and scrub the flat mesh filter beneath it. If cleaning the filter does not fix it, the drain pump is blocked or the drain hose is kinked.

Affected Models

Bosch 300 Series Dishwasher
Bosch 500 Series Dishwasher
Bosch 800 Series Dishwasher
Bosch SHPM88Z Series
Bosch Silence Plus Series

Common Causes

Filter assembly at the bottom of the tub blocked with food debris, grease, or broken glass
Drain hose kinked behind the dishwasher or not elevated enough to prevent backflow
Drain pump impeller blocked by a piece of food, glass shard, or label from a dish
Drain hose not connected correctly to the sink drain or garbage disposal
House drain or sink P-trap blocked, preventing water from leaving the dishwasher

How to Fix It

Clean the filter assembly

Open the dishwasher and remove the bottom rack. At the bottom of the tub, twist the cylindrical filter anti-clockwise and lift it out. Rinse under running water. Also lift out the flat mesh filter beneath it and scrub both under a tap with a soft brush.
Check the drain hose

Pull the dishwasher out slightly and check the corrugated drain hose at the back. It must not be kinked or flattened. The hose must loop up to counter height before connecting down to the sink drain — this prevents backflow siphoning the water out.
Check the garbage disposal

If your dishwasher drain hose connects to a garbage disposal, run the disposal for 30 seconds to clear any food blocking the drain inlet. Also check that the knock-out plug was removed when the disposal was installed.
Check for standing water at the base

Look inside the bottom of the tub after the cycle. A small amount of water (a few centimetres) is normal — it keeps the door seal moist. Water covering the filter completely means the drain pump is not clearing it.
Run a drain cycle

Press and hold the Cancel/Drain button (or select the Drain programme if your model has one) to force a drain cycle. If you hear the pump run but water stays, the pump impeller is blocked. If no pump sound is heard, the pump motor has failed.

When to Call a Professional

If cleaning the filter and checking the drain hose does not resolve the issue, the drain pump is blocked or has failed. A Bosch-certified technician can access and clear the pump without risk of water damage.

Frequently Asked Questions

Bosch dishwasher has standing water but no error code — why?

A partially blocked filter or a slow drain does not always trigger an error code. Clean the filter and check the drain hose even if no error code is displayed.

After I cleaned the filter, the Bosch dishwasher still won't drain — what next?

The drain pump impeller is likely blocked by a small hard object such as glass or a fruit stone. The pump is accessed by removing the filter and reaching into the sump — or by removing the lower spray arm and tub base.

Bosch dishwasher drains slowly — is that a problem?

Slow draining means a partial blockage in the filter or drain hose. Left untreated, slow draining leads to full blockage and eventually triggers an E24 error. Clean the filter and check the hose.