Inditex, Zara's parent company, recorded a 9% increase in sales to €2.218bn (£1.7bn) in the first quarter of its financial year. It also benefited from the strength of the euro to edge slightly ahead of Gap which saw its revenues fall by 10% and recorded sales of €2.169bn in the same period.
The difference may be tiny, but Inditex claims it is significant: for the first time the Spanish group has inched past its American rival.
The group, whose high street store Zara has led the charge, hopes to consolidate its lead over rivals later in the year as it continues to expand overseas in spite of the economic downturn.
It is three years since Inditex overtook H&M, to become the biggest clothing retailer in Europe. But the rapid growth is nothing new to a company which first started in 1963 in the bedroom of chairman Amancio Ortega's home in Galicia, northwest Spain, making bathrobes.