The U.S. Environmental Protection Agency (EPA) has revised its specification for tank-type toilets to earn the WaterSenselabel, reflecting evolving technologies and changes in the marketplace. To address the fact that many consumers don't always know how to flush a dual-flush toilet to use less water, EPA has updated the criteria for dual-flush toilets that offer both a full-flush and reduced-flush mode, to ensure that even the full flush saves water.

The WaterSense Specification for Tank-Type Toilets, originally released in 2007, was last updated in 2014. WaterSense labeled dual-flush toilets were previously required to meet a maximum effective flush volume of 1.28 gallons per flush (gpf), which was calculated by averaging two reduced-flush volumes and one full-flush volume. After EPA considered feedback from interested parties and data on dual-flush toilets use, the specification now establishes a singular maximum flush volume requirement of 1.28 gpf for either dual-flush or single-flush toilets.

In addition to the dual-flush criteria update, Version 2.0 of the WaterSense Specification for Tank-Type Toilets includes minor revisions for clarity and consistency with other WaterSense specifications.

The Version 2.0 specification will take effect on July 1, 2025. EPA recognizes that the revisions will impact the certification status of dual-flush toilets with a full-flush volume over 1.28 gpf, which could affect some incentive programs offered by utilities and other WaterSense partners. To determine which dual-flush toilets are labeled, consumers can visit the WaterSense Product Search Tool at www.epa.gov/watersense/product-search. Visit the WaterSense website for more information about the transition timeline of the specification and to learn how this will impact currently certified models.

WaterSense, a partnership program sponsored by EPA, seeks to protect the future of our nation's water supply by offering people a simple way to use less water with water-efficient products, new homes, and services. Since the program's inception in 2006, WaterSense has helped consumers save a cumulative 7.5 trillion gallons of water and more than $171 billion in water and energy bills.