By Rajwa Quasim
Starbucks is facing a proposed class-action lawsuit filed by customers who allege that eight protein beverages marketed as “sugar-free” contain significant amounts of sugar and therefore should not carry the label.
The lawsuit was filed Friday in federal court in Seattle on behalf of three consumers from California, New York and Washington. The plaintiffs accused Starbucks of false and deceptive advertising and alleged that the company violated federal labeling rules by describing the beverages as sugar-free even though they contain sugar.
Steve Berman, co-founder of the law firm Hagens Berman, said, “Consumers avoid sugar for various reasons, whether that be general health, diabetes and blood glucose levels or other factors, and for many, a staunch mislabeling like this is significant.”
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“No reasonable person” would expect a product labeled “sugar-free” to contain that much sugar, the lawsuit states.
The eight Starbucks beverages named in the lawsuit are Sugar-Free Vanilla Protein Latte, Sugar-Free Caramel Protein Latte, Sugar-Free Vanilla Protein Matcha and Sugar-Free Caramel Protein Matcha, along with iced versions of each.
For example, Starbucks’ U.S. website listed a 16-ounce (0.5-liter) Sugar-Free Caramel Protein Matcha as containing 16 grams of sugar and a 20-ounce (0.6-liter) version of the same drink as containing 21 grams of sugar.
The company said each beverage is made without added sugar, meaning the sugar listed in the nutritional information comes from ingredients that naturally contain sugar. The company also said it uses sugar-free syrups for flavoring.
A Starbucks spokesperson said, “Starbucks has consistently and clearly provided information about its protein beverages, sugar-free options, customization choices, and nutritional content across product announcements, menus, marketing materials, Starbucks.com and the Starbucks app, and we intend to vigorously defend ourselves.”
The spokesperson added, “We believe these claims have no merit.”
The plaintiffs argue that federal rules prohibit a “sugar-free” claim for beverages containing more than 0.5 grams of sugar per 12-ounce serving. They also allege that Starbucks failed to provide certain federally required disclosures concerning the drinks’ calorie content and weight-control implications.
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The lawsuit seeks unspecified damages and asks the court to prevent Starbucks from using the “sugar-free” label on beverages that contain sugar.
According to Reuters, the case is among several lawsuits filed against food producers alleging that product labels do not accurately reflect their sugar content.
Starbucks introduced its protein drinks in September 2025 as part of its updated “Back to Starbucks” menu, which also targeted growing demand for protein and other functional beverages.