Turn off the water supply at the toilet before you flush again. The valve is on the small line behind the bowl. Turn it clockwise until it stops.
Then look at the floor. If the water is still in this one bowl, you have a clog and the next step is drain cleaning. If water is already spreading across the floor, or another fixture is backing up too, that is emergency plumbing.
Which call is this?
One toilet, water still in the bowl: drain cleaning. Water on the floor, or more than one fixture backing up: emergency plumbing. Both end at a service request.
1Turn the water off
An overflowing toilet keeps filling until the supply stops. The shutoff for that bowl is separate from the main house valve. Use the toilet valve first.
Do this in order:
- Stop flushing. Another flush is what pushes the water over the rim.
- Find the shutoff on the wall or floor behind the bowl, on the thin supply tube.
- Turn it clockwise until it stops. The tank should stop refilling.
- If that valve will not turn, or water is still coming, shut off the main water to the house and book help.
Lay down towels only after the water is off. Mopping while the bowl is still filling just moves the water around.
2One toilet, or water on the floor
Those are two different jobs. The first is a clog in this fixture. The second is water already leaving the bowl, or a backup that is not limited to this toilet.
Stay with drain cleaning if:
- •The water rose in this bowl and stopped once the valve was off.
- •The tub, shower, and other toilets are not backing up.
- •A few plunges, with the water already off, do not drop the level.
Book emergency plumbing if:
- •Water is on the floor, the baseboard, or running into another room.
- •Water keeps coming after the toilet valve is off.
- •A second fixture is gurgling or backing up at the same time.
3What not to do while it is overflowing
These make a bowl of water into a wet floor, or they make the clog harder to clear.
- •Do not flush again to "see if it goes down."
- •Do not pour chemical drain cleaner into a bowl that is already full. It sits there, and it splashes if the toilet is plunged.
- •Do not keep plunging if water is spilling over the rim. Shut the valve off and stop.
If you flushed an object and the bowl is not overflowing
That is a different problem. Use what to do if you accidentally flushed something. This page is for water that is rising or already on the floor.
Which visit to book
Pick the page that matches what you see after the water is off.
- 1Drain cleaning: one toilet is clogged and the water stayed in the bowl.
- 2Emergency plumbing: water is spreading, or more than one fixture is backing up.
- 3Request service or call (774) 226-6062: say whether the water is still in the bowl or already on the floor. Shop hours are Monday–Friday, 7:30 AM–4:00 PM, Saturday by appointment.
Toilet overflow FAQs
What should I do first if the toilet is overflowing?
Turn off the water supply at the toilet. The shutoff is usually on the wall or floor behind the bowl, on the small supply line. Turn it clockwise until it stops. Do not flush again.
When is an overflowing toilet just a clog?
If the water rose in this bowl and stopped once you shut the valve off, and no other fixture is backing up, treat it as a clog. That visit is drain cleaning.
When should I book emergency plumbing instead?
Book emergency plumbing if water is already on the floor, if it keeps coming after the toilet valve is off, or if a tub, shower, or another toilet is backing up at the same time.
Should I keep plunging an overflowing toilet?
Plunge only after the water is off and the bowl is not still spilling. If a few plunges do not drop the water, stop. More flushing pushes water onto the floor.
If the water is already out of the bowl
Leave the toilet valve off. Book emergency plumbing when water is on the floor or another fixture is backing up. If it is only this toilet and the water stayed in the bowl, book drain cleaning. Tell us which one it is so the tech brings the right machine.