Interstate 80 Business (Sacramento, California)

Interstate 80 Business (I-80 Bus), called the Capital City Freeway in its entirety and also known as Business 80, is a business loop of Interstate 80 (I-80) through Sacramento, California, United States. The route is also colloquially referred to as "Cap City Freeway" and "Biz 80". The entire route is a freeway.

It originally carried mainline I-80 through Sacramento until the early 1980s. The eastern half, originally known as the Elvas Freeway, was initially grandfathered into the Interstate Highway System; however, plans to upgrade or realign this portion to meet Interstate Highway standards were canceled. As such, the I-80 designation through Sacramento was moved to a northern bypass of the city that had previously been signed I-880, and the former routing was then designated as Business 80.

I-80 Bus then consisted of two connected segments. The western segment ran concurrently signed with US Route 50 (US 50) and also carried the unsigned designation of I-305. The eastern segment was assigned the unsigned designation of State Route 51 (SR 51). After travelers complained that I-80 Bus was difficult to follow, it was named the Capital City Freeway in 1996. As part of a resigning project which commenced in 2016, references to I-80 Bus on the western segment were being removed, subsequently leaving that portion only signed as US 50. The California Department of Transportation (Caltrans) however still lists the entire route under one I-80 Bus exit list.