KMart Halloween Costumes Sale + Coupon This post may contain affiliate links. See my disclosure policy for details.October 3, 2011 By Ann-Marie Leave a Comment If you're new here, you may want to subscribe to my email updates or my RSS feed. Thanks for visiting!There’s no need to pay hundreds of dollars for a Halloween costume! Head to Kmart where all Halloween costumes are on sale 25% off, plus use coupon code KBOO to save another $5! Coupon code expires 10/8/11. This post may contain affiliate links. By using these links you support my site – thank you! See my disclosure policy here.