Research firm The NPD Group estimates that active clothing accounted for 28 per cent of total apparel dollars spent in the 12 months ending May 2020, up 4 percentage points from 24 per cent of the apparel market in the 12 months ending May 2018.

And many of these athleisure sales are happening online. Within the Digital Commerce 360 Top 1000, 250 merchants sell apparel. Within this group, 23 retailers primarily sell athleisure.

The 23 merchants collectively grew online sales 19.1 per cent year over year in 2019, which is faster than the Top 1000 apparel retailers’ online collective growth of 13.7%. The 23 merchants that focus on athletic apparel include some of the largest online merchants such as Nike Inc., TheNorthFace.com (part of VF Corp.), lululemon Athletica Inc. and Under Armour, all ranked among North America’s 100 leading retailers in online sales.

Digital Commerce 360 estimates that for the 23 merchants that focus on athleisure apparel, their total web sales in 2019 generated 19.5 per cent of the online apparel sales of the Top 1000. This means that even though these retailers only represent 9 per cent of Top 1000 apparel merchants, they generated one-fifth of apparel sales.

In total, Digital Commerce 360 counts 93 more Top 1000 apparel merchants that sell apparel in some way. This means, of the Top 250 online apparel merchants, 46.4 per cent of them sell athletic clothing in some way. And that 20 per cent of apparel sales just from athleisure-focused merchants is likely even higher when factoring in athleisure sales from these 93 apparel merchants.