Some Starbucks Employees Aren't Happy With the New Dress Code Some Starbucks employees are walking out over the changes.

Last month, Starbucks announced on its blog that it was changing its dress code in all U.S. stores to allow the "iconic green apron to shine."

The new dress code went into effect on Monday. Baristas can only wear a black shirt (long-sleeved crewneck, collared, or button-up) on top and any shade of khaki, black, or blue denim "bottoms."

Related: 'We're Not Effective': Starbucks CEO Tells Corporate Employees to 'Own Whether or Not This Place Grows'

Now, Starbucks Workers United, a labor union representing more than 10,000 workers from more than 570 stores, says that hundreds of employees from 50 U.S. locations have walked off the job since Sunday in protest.

Workers United alleges the dress code has "materially differed" from a previously reached tentative agreement, per the complaint seen by Bloomberg. In a statement, a union delegate said the policy change "puts the burden on baristas, many of whom are already struggling to get by, to buy new clothes or risk being disciplined."

Meanwhile, Starbucks told Bloomberg that it's business as usual in stores, and the disruption has not affected operations. The coffeehouse also noted that the dress code change is "simple."

"Wear a black shirt, either your own or one we provide," the company said in the statement.

Related: Starbucks Is Limiting Mobile Orders to Reclaim the Coffeehouse's 'Connection' With Customers

^{Shirts like this will no longer be allowed under the green apron. Gabby Jones/Bloomberg | Getty}

The two sides have been negotiating a contract for years. The most recent offer was rejected in April, per Reuters.

Starbucks has more than 40,000 stores worldwide, with around 17,000 in the U.S. As of September 2024, there were around 200,000 employees in company-operated U.S. stores.

Starbucks has used the green apron as its symbol since 1987.