By Christina Shanahan
Updated Sep 02, 2014 @ 7:15 am
Credit: Courtesy

Cleaning out your closet to make room for those cozy fall pieces? Us too! Thanks to a new partnership between cool-girl brand Madewell and Blue Jeans Go Green, you can trade in your old denim duds and earn cash toward a new pair of blues. The best part? Your retired pieces will be put to good use.

Founded after Hurricane Katrina, Blue Jeans Go Green began working with Habitat for Humanity to provide denim insulation for homes being rebuilt in affected areas. Today, the organization is continuing the effort across the United States. To contribute, just find your closest Madewell store, then bring your used jeans to the register. As a thank-you for contributing to the cause, Madewell will reward you with $20 off your purchase of a new pair.

And there's more! When you're ready to rock your new indigos, snap a selfie and share your look on Instagram before September 21, 2014 using hashtags #denimmadewell and #contest for a chance to win a $1,500 Madewell gift card. Five runners-up will score $250 gift cards, and all the winners will be featured in an exclusive Artifact Uprising card set, available at select Madewell locations this fall. Go ahead, get 'gramming!