Hayley Barna & Katia Beauchamp

Founded in 2010 by Harvard Business School grads Barna and Beauchamp, Birchbox providers its female users with four to five beauty samples for $10 a month. The startup popularized the subscription box trend, but don't categorize it as such. The monthly packages enable bite-size discoveries, leading more than half of all subscribers to purchase full size products on their website. Birchbox has raised $11.9 million to date and launched its men's line (with a higher price point of $20 per month) in April 2012. It then acquired Parisian JolieBox the following September, allowing easy expansion into France, Spain and the UK, growing its user-base upwards of 400,000.