Once Upon a Book Club Memorial Day Deal: Save 15% On Subscriptions! Last updated by Hello Subscription on May 24, 2020. Memorial Day Subscription Box Deals / Subscription Box Coupons & Deals / Once Upon a Book Club Coupons Hello Subscription may earn compensation via links in this post. Read the full disclosure Save for Later Notification Once Upon a Book Club has a Memorial Day sale! Take 15% off your new subscription, starting with the June box, with promo code 3DAY at checkout! This coupon code is active on longer-length subscriptions! Check out all our Once Upon a Book Club reviews to find out more about this subscription box! Visit Once Upon a Book Club to get this deal!