Starbucks has been hit with a consumer class-action lawsuit accusing the coffee chain of falsely marketing eight "sugar-free" protein beverages that actually contain significant amounts of sugar. The suit was filed on October 2 in the U.S. District Court for the Western District of Washington by consumer-rights firms Hagens Berman and Sterlington PLLC on behalf of three consumers from California, New York and Washington.
The complaint targets Starbucks' "Protein Beverages" line: eight drinks whose names begin with "sugar-free" — the Sugar-Free Vanilla Protein Latte, Sugar-Free Caramel Protein Latte, Sugar-Free Vanilla Protein Matcha and Sugar-Free Caramel Protein Matcha, plus iced versions of each. According to the lawsuit, the beverages contain 13 to 21 grams of sugar per 20- or 24-ounce venti serving, the sugar coming from lactose naturally present in milk. Starbucks' own U.S. menu lists a 16-ounce Sugar-Free Caramel Protein Matcha at 16 grams of sugar and the 20-ounce version at 21 grams — compared with 11 grams in a single Reese's peanut butter cup. The American Heart Association recommends 25 grams of sugar per day for women.
The plaintiffs' central argument rests on federal labeling rules: a beverage containing more than 0.5 grams of sugar per 12-ounce serving cannot be called "sugar-free." "No reasonable consumer would understand a beverage named 'Sugar-Free' to contain 13 to 21 grams of sugar per serving," the lawsuit states. The consumers also accused Starbucks of capitalizing on the desire of 75% of Americans to reduce or eliminate sugar consumption, and of failing to include federally required disclaimers that the drinks are not low-calorie foods or intended for weight control.
A Starbucks spokesperson said in an email that the claims have no merit. "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 said. The company said the sugar comes from the protein-boosted milk it uses, that it adds no sugar to the drinks, and that flavoring comes from sugar-free syrup.
"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," said Steve Berman, co-founder and managing partner of Hagens Berman. Reuters notes that food producers are routinely sued for alleged false advertising, including dozens of recent cases challenging "sugar-free" or "zero sugar" claims for products containing the sugar substitute allulose. The protein beverage line launched in September 2025 as part of Starbucks' "Back to Starbucks" menu update; the company says venti servings run 270 to 340 calories. The plaintiffs seek unspecified damages and restitution for false advertising and violations of state consumer protection laws in New York, California and Washington.