Business U.S. 6 is a 4-mile loop through the city center of Warren, Pennsylvania. In 1989, a freeway bypass for U.S. was completed on the southside of the Allegheny River, while the original routing plus a connecting bridge were designated as a business loop. Except for brief stay as Ludlow Street near its western terimus, the route mostly follows Pennsylvania Avenue. It is cosigned with U.S. Route 62 for the westernmost mile of its journey.
Business U.S. 6 is a 2-mile loop through the borough of Tunkhannock, Pennsylvania. The route was signed in 2000, as a wider (but still two-lane) by-pass was constructed along the Susquehanna River to avoid the narrow old alignment. The business loop consists of Tioga Street, the main artery of the town.
Business U.S. 6 is a 14-mile loop through northern suburbs of the city of Scranton, Pennsylvania. The route was created in 1999, after a freeway bypass was constructed. The route begins as a four-lane undivided highway, featuring a variety of businesses but avoiding the centers of suburbs like Dickson City and Blakely. It then becomes a two lane route and skirts north of the narrow suburban finger by traveling through Archbald Pothole State Park and Pennsylvania forestry land. Upon entering Carbondale, the route dips south back into suburban development and serves as a narrow two-lane street for the remainder of its journey.
Beginning at where US 6/202 meet NY 9D at the eastern foot of the Bear Mountain Bridge, U.S. Route 6/202 Alternate is a 10.5-mile (16.9 km) signed bypass of the segment of US 6/202 known as Bear Mountain Bridge Road, a sharply winding route to US 9 in Peekskill. US 6/202 Alternate follows NY 9D north to NY 403, then US 9 south, ending at the US 6/9/202 traffic circle. This bypass is an important route for commercial vehicles which cannot traverse Bear Mountain Bridge Road, though they are permitted to do so.
In Scituate, US 6 splits into bypass and business alignments. The business alignment runs further south along the old turnpike, and is mostly signed as US 6 without a banner. The bypass is signed mostly as BY-PASS US 6 on sign assemblies but as bannerless US 6 on green guide signs. Most maps and information takes US 6 along the bypass.
The business and bypass cross Route 102 soon after splitting. The western half of the bypass is a two-lane limited access road, with one grade separation — under Gleaner Chapel Road — and one intersection — at Route 102. This newer section ends as it merges with Route 101, once the Rhode Island and Connecticut Turnpike, and now called Hartford Pike. The two parallel alignments cross the Scituate Reservoir and Route 116 before they merge near the east edge of Scituate. This merge was the east end of the Foster and Scituate Turnpike, and was the east end of Route 101 until the early 2000s (when it was truncated to the merge with US 6 Bypass). (The Rhode Island and Connecticut Turnpike continued to the Olneyville section of Providence, where it is known as Hartford Avenue.)
U.S. Route 6A is an alternate route of U.S. Route 6 in Rhode Island. The route begins at US 6 and Interstate 295 in Johnston and follows Hartford Avenue 2.6 miles (4.2 km) through the city. US 6A continues into Providence, traveling 1.3 miles (2.1 km) along Hartford Avenue to its terminus at US 6.
US 6A previously carried mainline US 6 until around 1990, when US 6 designation was moved to the Dennis J. Roberts Expressway replacing the expressway's previous designation of Route 195.
A bypass route exists in Bourne, Massachusetts, where the mainline of Route 6 is on the other side of the Cape Cod Canal. However, it is not well signed, and this stretch of road is commonly referred to as Sandwich Road.
U.S. Route 6A originally connected Woodbury to Willimantic. West of Meriden, this was the original alignment of US 6. When US 6 was reassigned to the former US 6A from Plymouth-Farmington, this became US 6A. This US 6A was subsequently extended through Meriden to Willimantic along modern Route 66. An expressway upgrade was planned for this US 6A. Only a portion of the highway was built and is now Interstate 691.