Business routes of Interstate 40

Interstate 40 Business marker Interstate 40 Business marker
Interstate 40 Business
Location
CountryUnited States
Highway system

Interstate business routes are roads connecting a central or commercial district of a city or town with an Interstate bypass. These roads typically follow along local streets often along a former U.S. Route or state highway that had been replaced by an Interstate. Interstate business route reassurance markers are signed as either loops or spurs using a green shield shaped and numbered like the shield of the parent Interstate highway.

Along Interstate 40 (I-40), business routes are found in the five westernmost states through which I-40 passes, California, Arizona, New Mexico, Texas, and Oklahoma. The Interstate has no business routes along its passage through Arkansas nor Tennessee, and there once was a business route in North Carolina, but it was decommissioned in 2020.

Some states regard Interstate business routes as fully integrated within their state highway system, while other states consider them to be either local roads to be maintained by county or municipal authorities or a hybrid of state and local control.

Although the public may differentiate between different business routes by the number of the parent route and the location of the route, there is no uniform naming convention. Each state highway department internally uses its own designations to identify segments within its jurisdiction.

From central Oklahoma westward, the business routes often follow the historic alignment of the former U.S. Route 66 (US 66).