Tamaulipas is one of the 31 states of Mexico and is located in the central-northeastern part of the Mexican federation. It borders the U.S. state of Texas to the north, the Gulf of Mexico to the east, Veracruz to the south, San Luis Potosí to the southwest, and Nuevo León to the west.

The name Tamaulipas is derived from Tamaholipa, a Huastec term in which the tam- prefix signifies "place where." As yet, there is no scholarly agreement on the meaning of holipa, but "high hills" is a common interpretation. (However, a native population of Tamaulipas, now extinct, was referred to as the "Olives" during the early colonial period, which is a likely Spanish transformation on holipa.)

According to the 2006 census, Tamaulipas has a population of 3,024,238. Its capital is Ciudad Victoria. Other important cities include Reynosa, Matamoros, Nuevo Laredo and Tampico.