One of the busiest days of the year for the brand, Red Cup Day, will see more than 100 Starbucks outlets go on strike.
On Thursday, one of the chain's busiest shopping days of the year, employees at more than 100 Starbucks outlets that are unionised intend to go on strike.
113 sites where the strike is taking place will have protests.
Distributed by the organisers is a red cup with the Grinch's hand holding an ornament bearing the union's logo for Starbucks.
In its year-long organising campaign, Starbucks Workers United has only taken one other large-scale collective action.
The union claimed that the purpose of the strike is to draw attention to the company's alleged violations of labour laws and failure to fairly negotiate contracts.
Around 260 company-owned Starbucks outlets have approved unionisation under Workers United in the previous 12 months.
Workers at Trader Joe's and Chipotle Mexican Grill have taken similar steps as a result of the union push that made headlines.
Starbucks announced its readiness to begin contract negotiations in late September by sending letters to more than 200 locations.
The firm, according to Starbucks Workers United, has not been bargaining in good faith.