Stop the overflow
Close the supply valve
Turn the oval valve behind the toilet clockwise until it stops. The tank will stop refilling.
If the valve will not turn
Lift the tank lid and raise the float to stop the fill, then close the main shutoff.
Protect the floor
Lay towels down and keep the water from reaching carpet or the next room.
Wait before plunging
Let the bowl level drop a bit so plunging does not push more water over the rim.
Simple clog or something bigger?
- IfOnly this toilet is affected and a plunger clears itIt was a local clog. Turn the supply back on and watch the next few flushes.
- IfWater gurgles up in the tub or shower when you flushThe main line may be blocked. Stop using all fixtures and call a plumber.
- IfSeveral drains are slow at the same timeTreat it as a main-line problem rather than a toilet problem.
- IfThe toilet keeps clogging every few daysAsk a plumber to check the toilet and the drain line, possibly with a camera.
- IfWater leaks from the base after the overflowThe wax seal or flange may need attention. Avoid using that toilet until it is checked.
Why toilets back up in older homes
Wipes labeled flushable, paper towels and hygiene products are frequent causes of toilet clogs. In older Fullerton houses with cast-iron or clay sewer laterals, roots and buildup inside the line make it easier for those items to snag further down.
If a toilet was fine for years and now overflows regularly, the problem may not be the toilet at all. A camera inspection of the drain line is how plumbers usually check.
Clean up safely
Common questions
Is an overflowing toilet an emergency?
It is if the water will not stop or other drains are backing up. A single clog you can stop with the supply valve can usually wait.
Why does the toilet gurgle when the washer drains?
It often means the shared drain line is partly blocked or poorly vented. Have it checked before it becomes a backup.
Can a toilet overflow damage the ceiling below?
Yes. Water can travel under flooring and through the subfloor. Check the ceiling below and dry it promptly.
General information for Fullerton, not a quote or professional advice. In an emergency, call 911.