"People are suffering with the cost-of-living crisis. We need a pay rise, pay transparency and a voice," said one retail employee at the Glasgow Apple store.
"Apple’s repeated violations of the National Labor Relations Act have made a free and fair election impossible," said the Communications Workers of America.
Workers have filed an unfair labour practice report alleging that Apple requires them to attend meetings where managers convey overt anti-union messaging.
The script says unionization could result in "fewer opportunities" and reduced "flexibility" for workers and force Apple to pay "less attention to merit."
Workers at Apple's Grand Central store have affiliated with Workers United, a labour union that recently helped Starbucks employees in the U.S. unionize.