Kiwi Butter, Meet Irish Butter
Costco's Kirkland Signature grass-fed butter, long made only in New Zealand, will now also be produced in Ireland under a new contract with Tirlán, an Irish dairy co-op. The change was reported on October 21, 2026. The label used to say "Product of New Zealand," and Costco's website now lists the origin as New Zealand or Ireland. The back of some packaging now reads "Product of Ireland," and the site notes packaging varies by location.
It is the kind of change that most shoppers would not notice on the shelf, and the kind that Costco members notice immediately, because the butter is one of the warehouse's cult items.
Who Is Tirlán
Tirlán already sells its own grass-fed butter, Truly Grass Fed, at Costco, and it also supplies Ornua, the maker of Kerrygold. That makes the new deal a twist: the supplier behind a Kirkland butter that is priced below Kerrygold also feeds Kerrygold's parent company. One outlet reports the four-pack costs $10.99, about $4 less than Kerrygold. The report does not say how production will be split between the two countries, and it includes no official Costco statement.
Why Irish Butter
Irish dairy leans on pasture-based production, and grass-fed butter has a reputation for a yellower color and a more pronounced flavor than butter from grain-fed herds. Tirlán says it is responding to demand for private-label grass-fed butter. For Costco, a second supplier in a second country also reduces the risk of relying on one source.
What Fans Are Saying
Reactions are divided. Some shoppers see Irish butter as an upgrade. Others doubt the taste and texture have improved. In the r/CostcoWholesale subreddit, one user wrote, "The NZ one is better, just tasted them side by side." Another said, "The new one is way softer out of the fridge & has very little structure." A few social media users found the new butter too watery or soft, though the report notes it spreads easily when cold. Opinions were split on whether there is any real taste or texture difference.
The Packaging Complaint
The most contested change may be the wrapper. The tablespoon markings that were printed on the New Zealand packaging, which made measuring easy, are gone, and most commenters felt the packaging was a downgrade. For bakers who cut butter by the tablespoon, that is a real loss of convenience.
An Older Controversy, Not the Same One
Costco's butter has drawn complaints before. A December 2023 CBS News report covered members who said Kirkland butter was making baked goods fail, with pie crusts and meringue buttercream not behaving. That story never confirmed a recipe change, and Costco did not respond to CBS's request for comment. A Drexel food science professor said water content in churned butter can vary and could affect baking, and U.S. standards require butter to contain at least 80% milkfat, with American butter typically running 80% to 82%.
An Allrecipes writer who looked into the complaints could not confirm a change because she had no earlier version to compare. The new Irish sourcing is a separate development.
The Wider Market
Irish farmers' associations warn that local milk producers could see lower pay because of competition with Kerrygold, since a private-label butter from the same supplier sits next to it at a lower price. U.S. butter consumption has risen for over 25 years, reaching 6.8 pounds per person in 2024, which helps explain why every large retailer wants a strong butter offer.
It is unclear whether shoppers will keep buying the new butter. If the reaction stays negative, Costco could return to New Zealand-only production, though the company has made no statement either way.
How to Check What You Bought
Look at the origin line on the package or the carton label. If you bake, compare the two if you can find both. Butter with higher water content can change how dough spreads, so recipes that rely on cold, firm butter, such as laminated doughs and pie crusts, are where a difference would show first. If you cannot find the New Zealand version, a block of Kerrygold is the closest alternative at a higher price. Whichever you choose, keep notes on how your usual recipes turn out, since that is the most reliable test.
