EveryDIY.ca
All guides
PlumbingBeginner
Low riskRoutine

Fix a running toilet

A constantly running toilet wastes up to 750 L of water per day. Most fixes take 15 minutes and one $10 part.

Last reviewed May 31, 2026 by the EveryDIY.ca editorial team

Fix a running toilet
15–45 min $10–$30 CAD pricing

Diagnose

  • Flapper leaking: add food colouring to the tank; if colour appears in the bowl without flushing, replace the flapper.
  • Fill valve overshoots: water flows into the overflow tube — adjust the float or replace the fill valve.

Replace the flapper

  1. Shut off the water at the supply valve.
  2. Flush to empty the tank.
  3. Unhook the old flapper from the overflow tube.
  4. Snap on the new flapper, reattach the chain with about 1 cm of slack.
  5. Turn the water back on and test.

Cost

A universal flapper is $8–$15 at any Canadian hardware store. A full fill-valve kit runs $20–$30.

Need local help?

Need a licensed plumber?

Tell us what's happening. We'll connect you with a vetted local service provider.

Editorial note. Wear appropriate PPE. When in doubt — especially with electrical, gas, or structural work — hire a licensed Canadian tradesperson. See our safety policy.