RELATED: In-N-Out expands menu for first time in decades with addition of hot cocoa
The beloved fast food chain opened its doors on Oct. 22, 1948 in Baldwin Park.
In-N-Out is celebrating the day releasing its 2019 T-shirt in restaurants - along with an official party Nov. 17 at the Fairplex in Pomona.
The restaurant now has 334 locations in six states.