JACKSONVILLE, Fla. – Whataburger is celebrating its 70th anniversary and wants us all to have happy and full tummies! The burger chain is offering a buy one, get one free burger deal from now through Sunday, according to its website. The offer is only redeemable by presenting the offer when ordering by opening the barcode on the Whataburger app or online order. 1 Whataburger, and add-ons are an additional fee. Orders can be made by signing into an existing Whataburger account or creating an account by downloading the Whataburger App.