Why Does My Dishwasher Smell Like Rotten Eggs?

Check trapped food, filter/drainage and hot-water odor — while ruling out gas if it is plausible.

Updated September 15, 2026Safety-aware troubleshootingNo professional inspection implied

Quick answerRotten-egg odor in a dishwasher is often trapped food or stagnant drain water, but a hot-water sulfur odor can enter with the supply. If the smell exists in the kitchen even when the dishwasher is off and gas equipment is present, fuel gas must be ruled out separately.

Act before troubleshootingIf a fuel-gas leak is plausible, leave and contact the gas utility/emergency service from a safe place before appliance troubleshooting.

60-second diagnosis

Does the empty dishwasher smell when fully cold?
Is the filter visibly dirty?
Is standing water remaining after a cycle?
Does hot water at the sink smell similar?
Is a gas range or gas line nearby and does the odor exist when dishwasher is off?

Likely causes, ranked by fit

Food debris / dirty filter

Common

Best fit: Odor stays inside tub and filter has residue.

How to check: Inspect user-serviceable filter per manual.

What fixes the source: Clean filter, screen and accessible food-contact areas.

Drainage problem / standing water

Common

Best fit: Water remains in tub or odor worsens after idle periods.

How to check: Confirm whether cycle fully drains.

What fixes the source: Clear user-accessible filter; appliance/plumbing service if drainage path is faulty.

Hot-water sulfur odor

Possible

Best fit: Kitchen hot water smells similar outside dishwasher.

How to check: Compare hot and cold sink water.

What fixes the source: Evaluate water-heater/water supply source.

What to do now

Rule out gas if plausible.
Clean the filter according to the manual.
Confirm the unit drains fully.
Compare hot and cold water at the kitchen sink.

Do not do this

Do not mix bleach with acids/ammonia or add unapproved chemicals to the dishwasher.

When to call a professional

Use appliance service for persistent standing water or pump/drain faults; plumber for household drain issues; gas emergency service for suspected gas.

Questions people ask

Why does it smell after sitting overnight?

Food residue and stagnant water become more noticeable when the closed tub sits warm and damp.

Can hot water cause the smell?

Yes. If the same sulfur-like odor appears at other hot-water taps, the dishwasher may not be the original source.

Should I run bleach through it?

Only use products and procedures explicitly allowed by the manufacturer. Mixing chemicals or using incompatible products can be dangerous or damage the machine.

Primary safety/reference sources used on this guide

U.S. PHMSA — Recognizing and responding to natural-gas emergencies — Natural gas is odorized and may smell like rotten eggs; PHMSA advises leaving the area and avoiding switches, phones, flames and engines near a suspected leak.

This information is educational and cannot verify a leak, electrical fault, mold condition, water quality result, plumbing-code issue or appliance failure remotely. When there is immediate danger, follow local emergency guidance.