Starbucks on Monday announced a new test pilot program at its coffee shops in Colorado, encouraging customers to bring in their own personal cup.

The pilot program is running at 192 participating stores across the Centennial State and is aimed at reducing waste.

“We set a bold aspiration to become a resource positive company – to store more carbon than we emit, to eliminate waste and to conserve and replenish more freshwater than we use. This aspiration included setting ambitious 2030 targets to cut our carbon, water, and waste footprints in half,” Michael Kobori, Starbucks chief sustainability officer, said in a post announcing some of the company’s new tests to reduce waste. “Innovation is how we will build our next chapter, advance our planet positive impact, and boldly reimagine our future together.”

As an incentive to encourage customers to bring their own cup, Starbucks is giving 10 cents off the order. Rewards members would also get 25 bonus stars, up to three times per day.

The Seattle-based coffee chain said it chose Colorado as a test market for the program because customers in the state were already bringing in personal cups at a rate higher than the national average.

“We selected Colorado for this test due to the customers in this market having a tendency to be early adopters with personal cup use,” a Starbucks spokesperson told The Denver Gazette in an email. The spokesperson declined to share any data on the percentage of customers currently bringing in personal cups.

The test runs from April 10 to June 30, and Starbucks says it’s the company’s largest test on reusable cups it has ever run in the U.S.

“Only clean cups will be accepted, and Starbucks partners will not be able to clean cups for customers,” the Starbucks spokesperson said. “We appreciate our customers bringing their clean personal cup and reminding their barista that they have their personal cup with them when they place their order at the drive thru. This is another small way we’re inviting our customers to join us in our efforts to reduce waste in our communities.”

The spokesperson said Starbucks hopes to expand the program across the U.S. and Canada for every visit by the start of 2024.

The company said its goal is to “create a cultural movement towards reusables” by 2025, and in other markets it is testing a “borrow a cup” program in which drinks are sold in designated reusable cups which are later returned to stores and professionally cleaned.

“Through testing, our goal is to learn how to offer customers a way to shift from single use cups toward a reusable to-go-coffee experience, in a way that is convenient, easy and enjoyable, while also providing a standardized and barista-informed solution,” the Starbucks spokesperson said.