Costco's rotisserie chicken says "no preservatives." A new lawsuit says two ingredients on the back label say otherwise

Costco's $4.99 rotisserie chicken has carried "No Preservatives" signage for years, in stores and online. On January 22, 2026, two shoppers sued, arguing that claim was false the entire time — not because of some hidden ingredient, but because of two additives that were already printed on the back of the package.

The lawsuit

Johnston v. Costco Wholesale Corporation, filed by Bianca Johnston and Anatasia Chernov in the U.S. District Court for the Southern District of California (Case No. 3:26-cv-00403-AJB-AHG), alleges Costco "systemically cheated customers out of tens — if not hundreds — of millions of dollars" by advertising its Kirkland Signature Seasoned Rotisserie Chicken as free of preservatives while it's made with sodium phosphate and carrageenan. The complaint argues both ingredients function as preservatives regardless of what Costco calls them: sodium phosphate buffers pH, chelates metal ions, and reduces fat oxidation — which inhibits microbial growth and spoilage — while carrageenan is used industry-wide to preserve texture and extend shelf life. Neither ingredient is a secret; both were already listed in the smaller-print ingredient panel. The claim, per the suit, is that the prominent "No Preservatives" signage created a false overall impression that overrode what the back label actually said.

Costco's response, given to USA TODAY after the suit was filed: "We use carrageenan and sodium phosphate to support moisture retention, texture, and product consistency during cooking. Both ingredients are approved by food safety authorities." The company has since removed the "no preservatives" signage from stores and its website.

Why this is a real gray area, not just semantics

Here's the part that makes this more interesting than a typical "gotcha" suit: the FDA's own definition of a preservative is built around purpose, not just chemical effect.

Under 21 CFR 101.22, a chemical preservative is "any chemical that, when added to food, tends to prevent or retard deterioration thereof," and a food containing one has to name it and state its function — "preservative," "to retard spoilage," "a mold inhibitor," and so on. But the same regulation doesn't require that label if an ingredient's declared purpose is something else, even if it has a secondary preserving effect. That's exactly the gap Costco's statement is standing in: sodium phosphate and carrageenan are legitimately used across the food industry for moisture retention and texture, and both can also slow spoilage as a side effect of doing that job. Whether that side effect is enough to legally require the word "preservative" on the label is precisely what a court would have to decide — this case hasn't been ruled on, and nothing here should be read as a final answer.

Not the only thing going on with this chicken right now

This is a different lawsuit than the one we covered last month — that one, Taylor v. Costco Wholesale Corporation, alleges chronic Salmonella contamination at the Nebraska plant that supplies the chicken. Worth keeping the two separate: one is about what's in the chicken and whether the label says so, the other is about food-safety testing at the plant that makes it. Costco disputes both, and neither has been decided in court.

What to actually do with this

Nothing here means the chicken is unsafe to eat, and sodium phosphate and carrageenan are both permitted, widely used food additives — this isn't a "get it off your plate" story. It's a labeling story: a $4.99 loss-leader built its reputation partly on being simple, and "simple" turned out to rest on a legal distinction between an ingredient's stated purpose and its actual effect. That distinction is exactly the kind of thing that's easy to miss reading a package in a warehouse aisle.

Where Tallow fits

"No preservatives" on a sign and "no preservatives" on the ingredient panel can be two different claims, and the only way to know which one you're getting is to read the actual list — not the marketing above it.

Tallow scans the ingredient panel itself, not the sign next to it, and flags additives like carrageenan and sodium phosphate in plain English so you can decide for yourself whether a "clean label" claim matches what's actually inside.

Eat clean. Make the label prove it.

This article describes allegations made in ongoing litigation that Costco disputes; nothing here has been proven or decided in court. This is not medical or legal advice. Primary sources: Johnston v. Costco Wholesale Corporation, Case No. 3:26-cv-00403-AJB-AHG, S.D. Cal. (complaint), KOMO News — Costco's statement and signage removal, and 21 CFR 101.22 — FDA chemical preservative labeling rule.