Birchbox Inc., an online retailer that sells beauty products by subscription, has raised $10.5 million in new capital.  

For $10 a month, the retailer sends customers four to five hand-picked samples of hair, makeup and skincare products. Visitors to Birchbox.com can then purchase full-size versions of their favorite products. The retailer offers products from more than 70 brands, including NARS, Benefit, Kiehl’s, Laura Mercier and Smashbox.

Launched in September of 2010 by Hayley Barna and Katia Beauchamp, Birchbox says it has increased its paid subscribers by 50% each month. “We are very excited about the opportunities this financing gives us as we continue to grow our business and expand our offerings,” Barna says. Birchbox did not say how it would use the funding.

Accel Partners led the funding round, which also included First Round Capital and other previous investors. “Birchbox is a leading pioneer in subscription e-commerce,” says Theresia Gouw Ranzetta, general partner at Accel. “The team has forged partnerships with some of the world’s leading cosmetic brands to give consumers a fun, monthly beauty sampling experience. We believe Birchbox has many opportunities for continued growth, and we look forward to aiding their success.”