Drain smells?

A sewer smell from one drain is often a dry trap in a sink, tub or floor drain that hasn't been used in a while, and running water refills it. If every drain smells, or they gurgle too, call a plumber.

Not sure which one it is? Snap your drain and we’ll narrow it down.

Is the drain slow rather than smelly?

That's a clog, not a smell problem. Clogged drain

Likely causes

Dry trap in a rarely used drain
Most commonEasy DIY
The smell comes from a guest bath, a floor drain or a seldom-used sink or tub. The trap's water seal has evaporated, so run water for a minute to refill it.
Buildup in the drain or overflow
CommonEasy DIY
A musty or rotten smell from a drain that is used often, and it's strongest right at the opening or the overflow hole. Clean out hair and sludge with gloves on, then flush with hot water.
Garbage disposal
CommonEasy DIY
The smell is only at the kitchen sink and is worst after using it. Food residue can collect in the disposal, so see the garbage disposal guide.
Clogged or blocked vent
Less commonCall a pro
A gurgling sound along with the smell, and drains that run slowly. Vents run up through the roof, so this usually needs a plumber.
Loose or failed trap connection
Less commonModerate DIY
A smell under the sink that comes and goes, sometimes with dampness or a slow drip at the trap joints. Wear gloves and eye protection if you open it.

Quick checks

Don't mix drain chemicals, and don't use one after another has failed. Never plunge or snake into standing chemical water. Wear gloves and eye protection if you open a trap. If you smell sewage and sewage is backing up, stop using water and call a plumber. A strong rotten-egg smell that isn't coming from a drain may be gas: leave the home and call the gas utility from outside.

Find which drain it is by sniffing near each one. If every drain smells, or they gurgle too, call a plumber.
Run water for a minute in any sink, tub or floor drain that hasn't been used lately, to refill the trap.
Clean the stopper or pop-up and the overflow hole of hair and sludge with gloves on, then flush with hot water.
At the kitchen sink, check the garbage disposal. See the garbage disposal guide.
Look under the sink for a damp or loose trap connection. Put a bucket under it before touching it.
If a toilet is the source, see clogged toilet in case something is backing up.

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No account, no phone number. Fixology’s AI reads your photo and tells you what’s likely wrong, how worried to be, and whether it’s a DIY fix.

Snap one of these:

the drain and any standing water
the trap under the sink
other drains nearby if they also smell or gurgle

Add a note or more photos next. Nobody calls you.

When to call a pro

Every drain smells, the smell comes with gurgling everywhere, sewage is backing up, or refilling the trap and cleaning the drain don't help. A plumber is $45–200 an hour (most $70–120), and a service call is $100–250, usually including the first hour. After-hours work adds $100–300 or more. If the problem is a slow drain instead, see clogged drain. For upkeep, see the drain guide.

Typical cost: No cost was sourced for fixing a dry trap, vent or smell. HomeAdvisor puts a plumber at an average of $341 ($182–501) for a typical job, with $45–200 an hour (most $70–120). A service call is $100–250, usually including the first hour, and after-hours work adds $100–300 or more. Refilling a dry trap with water costs nothing.

Sources: HomeAdvisor: How much does it cost to hire a plumber? (updated June 19, 2026)

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