Gurgling Sound From Toilet When Sink Drains
Situation summary
You hear gurgling or bubbling sounds from your toilet when water drains from the sink.
Immediate steps to limit damage
- Avoid running water in the sink for now
- Avoid flushing unless necessary
- Watch for slow draining or water backing up in any fixture
- If water starts backing up, stop using drains in that bathroom
Can you try anything here?
No.
Why you should not try anything
This situation often points to a shared drain or vent issue between fixtures. Basic attempts at one fixture may not reach the source of the problem. Running water to “test” drains can trigger backups or overflows.
When professional help is needed
- Water backs up into any fixture
- Multiple drains start draining slowly
- You smell sewage or see dirty water
- The gurgling happens consistently
- Gurgling continues after you stop using the sink and avoid flushing
- The toilet water level changes when the sink drains
Background (optional)
Gurgling can happen when air is pushed through water in a drain line. When it happens between fixtures, the shared drain line is often involved.