Starbucks workers and union members in England, Scotland and eight other countries are protesting on Wednesday in support of striking US employees, the company's US union told the BBC.
Starbucks Workers United last month launched a strike, which the union said has expanded to 3,000 baristas in more than 100 US cities. Workers are pushing for better pay and staffing, and for the coffee chain to resolve hundreds of unfair labour practice claims.
Starbucks said the strike affected less than 1% of the chain's shops, adding it had "no impact" on its overall business.
The international action will involve hundreds of workers and union supporters, Starbucks Workers United said.
The coordinated global action is unlikely to directly affect the company financially. It comes as the US union tries to ramp up pressure on the chain after negotiations stalled.
