Fixtures
Why Does My Toilet Keep Running, and How Do I Fix It?
A running toilet is almost always a worn flapper or a fill valve that's out of adjustment, and most homeowners can fix it in under twenty minutes with a cheap part.
Your toilet keeps running because the flapper — the rubber seal at the bottom of the tank — isn't sitting tight enough to stop water from trickling into the bowl, or the fill valve is topping the tank up past the point where it should shut off. Both are cheap, simple parts, and in most Toronto homes you can fix either one yourself in under twenty minutes with a screwdriver and a five to fifteen dollar part from the hardware store.
Why won't my toilet stop running?
Every toilet tank has a flapper that lifts when you push the handle, letting water rush into the bowl, then drops back down to seal the tank so it can refill and stop. If that seal doesn't fully close — because it's warped, coated in mineral buildup, or just old and stiff — water keeps leaking past it into the bowl, which tricks the fill valve into topping up the tank over and over. That's the running sound you hear, sometimes for hours. Toronto's harder water speeds this up, since mineral deposits build up on the rubber and stop it from sealing evenly.
How do I know if it's the flapper or the fill valve?
Take the lid off the tank and watch what's happening. If water is dribbling from the tank into the bowl even when nothing has been flushed, that's the flapper. If instead the water in the tank is running continuously and spilling into the overflow tube in the middle of the tank, the fill valve is set too high or has failed to shut off — you can usually fix this by adjusting the small clip or screw on the valve to lower the water level about an inch below the top of the overflow tube. If the chain connecting the handle to the flapper is tangled or too short, that alone can hold the flapper open a crack, so check that first since it costs nothing to fix.
Is a running toilet actually costing me money?
Yes, and often more than people expect. A toilet that runs continuously can waste a significant amount of water over a single day, and it shows up directly on your water bill from the city. It's one of the more common reasons homeowners in older buildings around Toronto — think prewar houses in the Junction, Leslieville, or Riverdale with original or long-since-replaced toilets — see a water bill that doesn't match their usage. If your bill has crept up and you can't explain it, check every toilet in the house for a faint hiss or trickle, especially overnight when everything else is quiet.
Can I fix a running toilet myself?
In most cases, yes. Universal flapper and fill valve kits are sold at any hardware store and are designed to fit the vast majority of standard toilets without needing to match brand or model exactly. Shut off the water at the small valve behind the toilet, flush to empty the tank, and swap the part following the instructions on the package. It's one of the more approachable plumbing repairs a homeowner can do without special tools.
When should I call a plumber instead of fixing it myself?
Call a plumber if you've replaced the flapper and fill valve and the toilet is still running, if the shutoff valve behind the toilet won't turn or is seized, or if you notice the tank itself is cracked or the toilet is old enough that replacement parts don't fit properly anymore. This is common in some of Toronto's older housing stock where toilets and their tank hardware haven't been updated in decades. A standard toilet repair typically runs $125–275 with GetFixHero, and if the issue turns out to be a full toilet replacement rather than a repair, a plumber can walk you through those options on the same visit.
Frequently asked questions
Can a running toilet cause damage besides a higher water bill? It's rare, but if the tank is overfilling because the fill valve won't shut off, water can eventually spill over the tank rim, which is worth watching for if the running sound is unusually loud or constant.
Why does my toilet only run for a few seconds every so often instead of constantly? That intermittent running, sometimes called "phantom flushing," is almost always a slow leak past the flapper — the tank drains just enough to trigger the fill valve to top it back up, then stops. It's the same fix as a fully running toilet, just a smaller leak.
Is it worth replacing an old toilet instead of repairing it? If you're replacing internal parts more than once every year or two, or the toilet is original to a much older home, a new toilet often uses less water per flush and can be the more practical long-term choice — a plumber can give you a straight answer once they've seen the unit.
A running toilet is one of the cheapest plumbing problems to ignore and one of the cheapest to fix — request a plumber or message us on Facebook. Free for homeowners, care of GetFixHero.
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