Free slider today at White Castle restaurants via promo code SLIDERDAY

Store

White Castle

Category

Restaurant Coupons

Posted

May 15, 2026 (May 15, 2026)

Promo code

SLIDERDAY

Where to use

Online or in store, with the promo code

Cost

Free. No account needed to use a coupon.

This White Castle offer was posted on May 15, 2026 in Restaurant Coupons. Enter promo code SLIDERDAY at checkout; if the store also honors it in person, the cashier can key it in. Offers like this usually run for a limited time, so use it soon. The newest White Castle coupons are listed below, and every one is also free in The Coupons App, with an alert the moment a new one arrives.