Christa Geraghty | 

National Slider Day 2025: Grab a Free Slider at White Castle, Krystal + More

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May is National Burger Month. White Castle Free Slider Day is right in the middle on May 15, followed by National Burger Day on May 28. When food holidays like these roll around, we expect to see free food deals. And, every year, White Castle takes the spotlight by offering a free slider to customers for White Castle Free Slider Day (also known as National Slider Day).

Here's where you can find free sliders on National Slider Day in 2025.

For more smart shopping tips and savings hacks, text HACKS to 57299.

Offers, prices, and local participation may vary.

National Slider Day is a one-day event with free and cheap sliders.

Although fast-food chain White Castle started National Slider Day back in 2015 as a way to honor its signature menu item, the slider, other restaurants have joined in to celebrate the miniature hamburgers with free or discounted sliders. Most reliably, White Castle gives out a free slider with coupon. 

National Slider Day will happen May 15, 2025.

National-Slider-Day-2025

Fast-food slider giant White Castle started National Slider Day (and arguably, the slider itself) in 2015, proclaiming it to be May 15. So every year, regardless of the day of the week, it’s the same date. This year, you can celebrate with cheap or free sliders on Thursday, May 15, 2025.

Use a coupon to get your free White Castle Slider on National Slider Day.

To get your free Original slider (no purchase necessary) from White Castle in 2025, you'll need to use promo code SLIDERDAY during checkout at WhiteCastle.com or in the White Castle app. For in-store orders, show this Free Slider coupon to the cashier on National Slider Day.

Other National Slider Day Deals

Confirmed

  • Dog Haus: This year, Dog Haus is offering a FREE slider when you order $10 or more on Slider Day.

  • Krystal: Krsytal is offering fans a free Original or Cheese Krystal with any $5 purchase on National Slider Day (May 15) when you use promo code SLIDERDAY at checkout online or in-app.

Predicted

  • Smalls Sliders: Rewards members can look for an exclusive free slider with purchase offer at Smalls Sliders on National Slider Day. Plus, look for an Instagram giveaway Smalls Rewards members can enter for a chance to win free sliders for a year.

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