A dual-flush or low-flow toilet will work best where there’s gravity to help it along, says Nguyen. Otherwise, consider the possible long-term issues with sewer blockage.

How Does Bill Gates's Ingenious, Waterless, Life-Saving Toilet Work? More than two billion people don't have access to safe, clean sanitation systems. This toilet might be a big step toward fixing ...

High-efficiency toilets come with a variety of options that could improve your bathroom experience.