US 63B runs north as Main Street, passing through the commercial district of the town before turning right onto Grand Avenue.

[5] After one block, the route turns south onto Main Street and runs through downtown Warren.

Passing historic structures, including the Bradley County Courthouse and Clerk's Office, Blankinship Motor Company Building, Warren Post Office, and the Ederington House (all NRHP listed).

[7] Shortly thereafter, the route was renumbered to US 63B when US 63 supplanted AR 15 as part of an extension south from West Memphis to Ruston, Louisiana; approved by AASHTO on October 2, 1999.

[10] The roadway continues northwesterly, paralleling the BNSF Railway tracks through a commercial part of town.

US 63B serves as the eastern terminus of Highway 230 (Church Street) near the center of town before continuing northwest to terminate at the parent route.

The two-lane road runs northwest, paralleling the BNSF Railway tracks and crossing under a freeway segment of US 67 and US 412 (with no connection) before entering Hoxie as Lindsey Street.

After passing through a residential section, US 63B crosses the Union Pacific Railroad tracks before intersecting AR 367; the two routes form a concurrency southbound as Texas Street for four blocks.

US 63B begins near the western city limits of Hardy at US 63 and runs east toward the Spring River as Main Street concurrently with US 62/US 412.

Shortly after beginning, US 63B has a junction ending the US 62/US 412 concurrency; US 63B continues eastbound alone into the Hardy Downtown Historic District.

[27] The change was approved by the American Association of State Highway and Transportation Officials on November 20, 2014.

It starts about 0.75 miles (1.21 km) north of Missouri Supplemental Highway ZZ, and locally is known as Bill Virdon Blvd.

Crossing Washington Ave near Court Square, the road changes names again to Broadway.

After running as Broadway for about 1 mile (1.6 km), the road turns toward the north again at Porter Wagoner Blvd., where the Garrett service station stands, and remains that name until it meets back with US 63 near the Wayhaven area of West Plains.

[34] The route began at Exit 43 on I-530/US 79; where US 63 joins the freeway eastbound and the northbound Olive Street continuing as US 63B.

Olive Street runs north, bridging Bayou Bartholomew and entering a residential section of the city.

US 63B next turned onto Convention Center Drive and briefly overlapping Highway 190 (5th Avenue/6th Avenue, a one-way pair) and crossing the Union Pacific Railway tracks before turning onto US 65B (Martha Mitchell Expressway) eastbound.

The route ran west as North Front Street through a residential area, paralleling the former Chicago, Rock Island and Pacific Railroad tracks, since converted to the Hazen Trail and the Railroad Prairie Natural Area.

[4] On February 6, 2008, the Arkansas State Highway Commission relinquished control of the roadway to local maintenance.

63B) is a former business route of 2.4 miles (3.9 km) in Marked Tree, Poinsett County, Arkansas.

[40] US 63B began at an exit along I-555/US 63 and the northern terminus of AR 149 in Marked Tree, a small town in the Arkansas Delta.

It ran northeast along Melton Avenue before curving northwest and paralleling the St. Louis–San Francisco Railway (Frisco) railroad tracks.

[48] The City of Trumann requested the Arkansas State Highway Commission add this segment to the state highway system as a city truck route, however adding routes within municipalities was not permitted initially.

On November 8, 1961, the Arkansas State Highway Commission designated the Johnson Avenue Extension as U.S. 63 City Route (US 63C).