A running toilet is one of those household problems people tend to ignore for longer than they should. At first, it just sounds like a small annoyance — a bit of water movement, a faint hissing sound, maybe the occasional refill noise long after no one has used it. Easy to put off. Easy to assume it’s not a big deal. But over time, it can become one. Because even a minor toilet leak can quietly waste a surprising amount of water, and in some cases, that means a higher bill for a problem that often turns out to be much simpler than people expect.

That’s the good news. A running toilet doesn’t always mean you need a plumber, expensive repairs, or some complicated DIY job involving tools and parts you’ve never heard of. In a lot of homes, the cause is something small inside the tank that has shifted, worn down slightly, or stopped sealing the way it should. And if that’s the case, there’s a good chance you can fix it yourself in less time than you’d think.

You just need to know what to look for first.