The one-day special offer is valid on the purchase of four single Classic Smashburgers.

The Classic Smashburger features a certified Angus Beef patty, American cheese, lettuce, tomatoes, red onions, pickles, Smash Sauce, and ketchup on a toasted bun.

Smashburger’s National Hamburger Day offer is valid at participating locations nationwide for one day only on Sunday, May 28, 2023.

National Hamburger Day is celebrated annually on May 28.

Image via Smashburger

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