A dishwasher that smells — musty, eggy, or like old food — almost always has food debris or standing water sitting somewhere it shouldn't. The good news: nearly every cause is something you can clean yourself, for free. Here's the order a tech works it.
Food and grease collect in the filter at the bottom of the tub. A dirty filter is the most common source of a dishwasher odor.
Check it: Remove the bottom rack, twist out the cylindrical filter at the tub floor, and wash it in hot soapy water. Wipe out the sump area underneath before putting it back. Do this monthly.
Bits of food lodge in the spray-arm holes, along the tub edges, and in the door gasket, and rot over time.
Check it: Clear the spray-arm holes with a toothpick, wipe the tub edges and the rubber door gasket/seal, and clean around the detergent door.
A partly-clogged filter or drain hose leaves water standing in the bottom that goes stagnant and smells; grease film in the hose adds to it.
Check it: Run an empty hot cycle with a cup of white vinegar on the top rack (and/or a dishwasher cleaner) to flush grease and freshen it. If water always stands in the bottom, see our "won't drain" guide.
A true sewer smell can mean the drain hose isn't looped high enough (needs a high loop under the sink) or the air gap is missing, letting sink-drain odor back up.
Check it: If it smells like sewer (not food), a tech or plumber checks that the drain hose has a proper high loop / air gap.
Almost always a free cleaning fix — the filter, spray arms, gasket, and a vinegar cycle solve the vast majority of odors. Only a drain-routing or standing-water issue needs a closer look.
In Middle Tennessee or the Baton Rouge area? We'll come to you, same-day. Anywhere else in the U.S.? Send a 10-second video, a real technician tells you exactly what's wrong for $50 (credited toward the repair), and we ship you the exact part. 24/7 — text, call, or upload anytime.
Almost always trapped food — most often in the filter at the bottom of the tub, plus the spray arms, tub edges, and door gasket. Clean the filter, wipe the gasket, and run a hot vinegar cycle. That clears most odors.
Pull and wash the bottom filter in hot soapy water, clear the spray-arm holes, wipe the door gasket and tub edges, then run an empty hot cycle with a cup of white vinegar on the top rack. Do the filter monthly to keep it fresh.
A sewer smell (vs food) usually means the drain hose isn't looped high enough under the sink or the air gap is missing, letting drain odor back up. That's a quick routing fix a tech or plumber handles.