Costco Sued Over Claims Its Chicken Contains No Preservatives — What Are the Risks?
Costco’s chicken allegedly contains two preservatives: sodium phosphate and carrageenan.
Published Feb. 2 2026, 2:46 p.m. ET

Costco shoppers can often be thought of as a discerning bunch, seeking quality food and beverage items at affordable prices. Though amid constant food product recalls, claims from animal welfare activists like Farm Forward regarding the unfathomable abuse that chickens suffer within Costco's supply chain, and more, it is a wonder why anyone still supports Costco.
The latest in a long line of dents in the Costco armor is a lawsuit alleging its chicken does, indeed, contain harmful preservatives.
Costco famously claims that its Kirkland Signature Seasoned Rotisserie Chicken product is free of preservatives, while shoppers proposing a class action lawsuit believe otherwise, stating that the rotisserie chicken does contain preservatives. Many consumers have been left wondering: how damaging to human health can these preservatives be?
Below, we report on the latest class action lawsuit proposed against Costco. Continue reading to learn all of the details of this lawsuit.
What are the health risks of the alleged preservatives in Costco rotisserie chickens?
According to a damning report in USA TODAY, consumers of Costco's Kirkland Signature Seasoned Rotisserie Chicken claim that the product contains two added preservatives: sodium phosphate and carrageenan.
According to a medically reviewed assessment of the health risks of sodium phosphate in Healthline, the U.S. Food and Drug Administration (FDA) recognizes sodium phosphate as safe for consumption.
You may be familiar with the FDA's "GRAS" label, which stands for “generally recognized as safe.” However, Healthline notes that consumers with various conditions are advised to avoid consuming food products that contain sodium phosphate as a preservative.
Such individuals who should avoid this preservative include those with kidney disease, intestinal tears or blockages, colitis or slow-moving bowels, heart failure, or an allergy to sodium phosphate.
According to a medically reviewed assessment in Healthline on the health risks of carrageenan, although it has received the GRAS designation from the FDA, this ingredient is not without controversy.
"Some research suggests that carrageenan may trigger inflammation, gastrointestinal ulcerations, and damage to the digestive system," per the article.
Furthermore, Healthline adds the disclaimer that while carrageenan is not considered carcinogenic (aka cancer-causing), poligeenan is, and "some researchers have proposed that carrageenan may degrade to poligeenan in the gut."
Costco chicken is at the center of a class action lawsuit.
Per USA TODAY, a proposed class action lawsuit was filed on Jan. 22 in the U.S. District Court for the Southern District of California. The lawsuit alleges that Costco’s Kirkland Signature Seasoned Rotisserie Chicken contains two added preservatives, despite the retailer claiming that its chicken contains "no preservatives.”
The lawsuit claims that Costco “has systemically cheated customers out of tens – if not hundreds – of millions of dollars by falsely advertising its Kirkland Signature Seasoned Rotisserie Chicken as containing ‘no preservatives.’”
As of Jan. 28, Costco has removed signage making reference to its rotisserie chicken product being free of preservatives.
"To maintain consistency among the labeling on our rotisserie chickens and the signs in our warehouses/on-line presentations, we have removed statements concerning preservatives from the signs and on-line presentations," Costco said, per USA TODAY.
"We use carrageenan and sodium phosphate to support moisture retention, texture, and product consistency during cooking. Both ingredients are approved by food safety authorities."
If the lawsuit doesn't turn you off from Costco chicken, perhaps this gruesome post from a Redditor will.
"This is what a bruise looks like when cooked. That bird had a very hard last day on earth. Bruise isn’t even enough of a word. That bird was maimed before death."
