From what I have seen, this is a somewhat rare opportunity to stack coupon codes at Gap stores. Use code SAVE30 to save 30% at Gap.com, OldNavy.com and BananaRepublic.com. Then, if you pay with a Visa, you can also use code VISAKIDS1 to save an additional 20%. If you spend $100, you'll get free shipping. This deal expires tonight, 7/27.