Which U.S. States Share a Border with Mexico?

The United States shares a 1,954-mile land border with Mexico. Four U.S. states form this international boundary, each with unique geography and border crossing dynamics.

The Four Border States

• California: Shares a relatively short border (approx. 140 miles) with the Mexican state of Baja California. Major crossings include San Ysidro (the busiest land port in the Western Hemisphere) and Otay Mesa.
• Arizona: Borders the Mexican states of Baja California and Sonora over approx. 370 miles. Key crossings include Nogales, Douglas, and Lukeville.
• New Mexico: Has the shortest stretch (approx. 180 miles) bordering the Mexican state of Chihuahua. Primary crossings are at Santa Teresa and Columbus.
• Texas: Claims the longest segment by far (approx. 1,254 miles) along the Rio Grande, bordering the Mexican states of Chihuahua, Coahuila, Nuevo León, and Tamaulipas. It hosts numerous major crossings, including El Paso, Laredo, McAllen, and Brownsville.

These borders are vital corridors for trade, migration, and cultural exchange, shaping the economy and demographics of the entire Southwest region.