Unionized Costco stores in the U.S. voted to authorize a strike. Here's everything to know about possible Costco strike locations and Arizona impact.

With a master agreement with the Teamsters set to expire in 10 days, affecting 18,000 of the retailer's workers, hundreds last week held practice pickets.

Despite Costco claims it has a stable “cared-for employee base,” over 18,000 employees disagree. Costco Teamsters have voted to strike on January 31.