Mama Bird Box Labor Day Coupon: Save Up to $20! Posted by Hello Subscription on August 31, 2017. Subscription Box Coupons & Deals / Mama Bird Box Coupons Hello Subscription may earn compensation via links in this post. Read the full disclosure Save for Later Notification Mama Bird Box has a Labor Day Sale! Use the code:* JUSTPUSH1 to save $5 on 1 box. JUSTPUSH3 to save $10 on 3 boxes. JUSTPUSH6 to save $20 on 6 boxes.