Gap and Old Navy: 20% off Your Purchase December 10, 2010 This post may contain a link to an affiliate. See my disclosure policy for more information. Old Navy* and Gap are both offering up 20% off any purchase! Here are the coupon codes: Old Navy: Use coupon code ONGIFT20 today only Gap: Use coupon code GAP20 through 12/12/10 **Don’t forget to go through ShopAtHome! You’ll earn 8% cash back on your Old Navy and Gap purchases. *Excludes everyday steals and sweaters.