On The Border Mexican Grill, also known as On The Border Mexican Grill and Cantina, is a chain of Tex Mex-style restaurants. They are considered to be casual dining. This restaurant chain has locations in Puerto Rico, the United States, Egypt and more. The chain and the brand were both formed in October of 1982. It was founded in Dallas, Texas. This restaurant has more than 160 locations in the United States alone and are known for their wide selection of food and drinks, including tacos, fajitas, burritos, and their numerous styles of margaritas.