Half-year turnover report indicated like-for-like growth of 1.2%.
The online retailer is benefiting from a post-referendum slump in sterling.
Europe accounts for $11.67bn of the total figure, and North America for $7.93bn.
B by Ted Baker and Shock Absorber collections performed particularly well.
An explosion of fashionable lingerie and the wellness trend triggered the growth spurt.
Romantics splashed out on presents in the run up to Valentine's Day.
Lingerie sector outperformed clothing and electricals last month.
Valentine's Day helped boost sales in the sector, says IMRG.
IMRG managing director Justin Opie on the changing face of etailing.
The boutique offers walk-in retail and personal styling appointments.