13. Acetum Balsamic Vinegar

Another confirmed partnership is with Acetum, which has been the provider of Costco’s balsamic vinegar since 1999. 

You can easily find Acetum’s logo on Kirkland’s packaging, signifying this long-standing partnership to all their customers.

This collaboration ensures a high-quality product at a low price for Kirkland’s customers, as Acetum produces traditional balsamic vinegar that is typically aged for many years, resulting in a sweet and syrupy consistency.