A running toilet is more than a mere annoyance — it can affect your water bill, too. Here’s how to tackle this common issue.

Check the fill tube. Your toilet’s fill tube is relatively small and connects between the overflow tube and the fill valve. Its purpose is to shoot water into and down the overflow tube as the tank refills following a flush. If this tube comes unattached it won’t be able to deliver adequate water to the overflow tube and your toilet won’t be able to properly refill. Reattach the fill tube and ensure it sits about an inch above the top rim of the overflow tube.

Adjust the float. The adjustable float in your toilet tweaks the water level in your toilet’s tank. It may be ball or doughnut shaped. When your toilet’s float is either too high or too low, your toilet will run continuously due to the fill valve not shutting off, or it will simply produce a weak flush, respectively. Fix the float by twisting the screw or sliding the clip along the float ball’s rod to free it and then adjust the height of the float within the toilet’s tank as necessary, moving the float either up or down. Check the toilet’s water level after your adjustment by flushing the toilet. Repeat float adjustment as necessary.

Tweak the flapper chain. The flapper in your toilet closes when necessary to keep water from continuing to fill the bowl unnecessarily. A flapper chain that is too short will keep the flapper from closing, while a flapper chain that is adjusted to be too long will keep the flapper from opening entirely properly. Tweak the flapper chain’s linkage so that there’s just a bit of slack when the flapper is in its closed position.

Replace the fill valve. Over time, a fill valve may stop working, and this will cause the valve to fail to shut off. A fill valve that doesn’t shut off will cause the toilet to run. In this instance, be sure to close the water supply at the shutoff valve under the tank and head to your local hardware store to purchase a replacement valve. Always check with a store employee, but most fill valves will fit most toilets.

Switch out the flapper. Turn off the water to the toilet before proceeding, then remove the old flapper and take it with you to your local hardware store this time, as finding a proper flapper replacement is a bit more involved than simply plugging in a new fill valve. Ensure you’ve made note of the kind of toilet you possess before seeking aid at the hardware store in finding a new flapper. If you do not find a flapper specifically tailored for your toilet, you should be able to opt for a “Universal” flapper. If the new flapper does not keep your toilet from running, you’ll need to opt for another flapper model.