WaterSense is a voluntary label run by the US Environmental Protection Agency. A WaterSense toilet uses 1.28 gallons per flush or less, which is 20% below the federal standard of 1.6 gallons, and must pass performance tests set by EPA.
Indian WCs can meet it. The label is earned by a specific model through independent certification, not by a country or a factory. What matters is whether that model passes the tests.
What the specification requires
As of October 2026, Version 1.2 of the WaterSense specification for tank-type toilets, released on 2 June 2014, is the version in effect. EPA published a Version 2.0 in May 2024 but has paused its effective date, and says Version 1.2 remains in effect until further notice.
The main requirements are:
- A maximum flush volume of 1.28 gallons (about 4.8 litres). Dual-flush models are judged on an effective flush volume under Version 1.2.
- Waste extraction: the toilet must clear 350 grams of soybean paste test media and four balls of toilet paper in at least four of five flushes.
- All the requirements of ASME A112.19.2/CSA B45.1, the North American standard for ceramic plumbing fixtures.
- Limits on how far the flush volume can be adjusted upwards after installation.
Now part of the North American standard
EPA notes that the waste extraction test and the adjustability tests started in the WaterSense specification and were later adopted into ASME A112.19.2/CSA B45.1. All toilets sold in the US or Canada must now pass the waste extraction test, and high-efficiency models must show limited adjustability.
How a model gets the label
Only products that complete third-party certification can carry the label. A licensed certifying body tests samples, reviews the product and lists it. The brand owner applying is usually the company whose name appears on the product, which may be you as importer rather than the factory.
If you sell under your own brand, ask the factory which models are already certified under another listing, and whether the certification can be extended to your brand. The certifier will explain the options.
What decides whether an Indian WC can pass
- Trapway design and glaze: a narrow or rough trapway fails the waste test at low volumes.
- Casting accuracy: small changes in the trapway from mould wear can change results between batches.
- The flush valve and fill valve: they must deliver the certified volume and resist being turned up.
- Consistency: certifiers carry out follow-up checks, so production must match the tested sample.
What to ask the factory
Ask for the WaterSense listing for the exact model and the certifier's name, then check it on EPA's product search. Ask for the ASME A112.19.2/CSA B45.1 report too, covered in cUPC and ASME certification. For other markets' limits, see toilet flush volume rules by country.
Next step
We check listings against the models offered, compare production pieces with the certified design, and witness flush tests where needed. Book a free sourcing review.