Tracked by Evreward since 2010, Kerastase offers coupons, cash back rebates and rewards, with savings as high as 30% off. Kerastase discount coupons are seasonal, appearing every three to four months, and are often more valuable than similar merchants. Even when Kerastase doesn't have a coupon, you can always get up to 26% cash back, and other great rewards, with every purchase.