Free Fries at McDonald’sMcDonald’s Is Giving Away Free Fries Today for National French Fry Day. The offer is available exclusively through the restaurant’s app, so you’ll have to download the McDonald’s app and register as a user to place your order. Access the offer through the “deals” tab at the bottom of the app. Valid 1x 7/13/20 from 10:30 AM local time to close at participating McDonald’s.