Southwestern U.S. States That Border Mexico

Four southwestern states share an international border with Mexico, forming a 1,954-mile boundary that shapes regional economics, culture, and politics:

• Arizona – 372-mile border featuring the Sonoran Desert and major crossings at Nogales, Douglas, and San Luis.
• California – 140-mile border, the shortest, including the busy San Ysidro/Tijuana crossing—the world's busiest land border crossing.
• New Mexico – 180-mile border through Chihuahuan Desert terrain with crossings at Columbus, Santa Teresa, and Antelope Wells.
• Texas – 1,254-mile border along the Rio Grande, the longest state-Mexico border, with 28 major crossings including El Paso/Ciudad Juárez and Laredo/Nuevo Laredo.

These borders facilitate extensive trade (over $1.7 billion daily in U.S.-Mexico commerce), cultural exchange, and binational communities, while also presenting challenges regarding immigration, security, and environmental cooperation.