Interstate 555 (I-555) is an Interstate Highway that connects Turrell, Arkansas, at I-55 to Jonesboro at Highway 91 (AR 91). Formerly known as U.S. Highway 63 (US 63), the highway was upgraded in the early 21st century to Interstate Highway standards. While I-555 is the second Interstate with all three digits the same to exist, it is the first to be signed as an Interstate. (I-444 in Oklahoma, which was the first highway, is unsigned.)