Interstate 540

Interstate 540 is a designation used for multiple highways in the United States, each serving a distinct regional function as a spur or bypass of Interstate 40. Most notably, I-540 exists in Arkansas and North Carolina, where it improves metropolitan connectivity and alleviates urban congestion.

In Arkansas, I-540 originally stretched from I-40 at Alma south through Fort Smith and Van Buren, terminating near the Oklahoma border. While much of this route has since been redesignated as part of Interstate 49, the I-540 designation still technically applies to a short spur south of Fort Smith connecting to U.S. Route 71 near the town of Greenwood. Historically, this corridor played a vital role in linking Northwest Arkansas to the Oklahoma border and beyond.

In North Carolina, I-540 serves as a partial loop around the Raleigh metropolitan area. Built to relieve congestion and spur development in the Research Triangle, the loop is gradually being completed in segments. Portions of the loop that remain under construction or unconnected are sometimes signed as NC-540, reflecting their transitional status. Once finished, I-540 is expected to form a full beltway around Raleigh, greatly improving regional mobility.