List of primary Interstate Highways

There are 71 primary interstate highways in the 48 contiguous United States as well as five former and one future primary interstate highway. This number does not include auxiliary Interstate Highways. }} ==Other regions==

In addition to the 48 contiguous states, Interstate Highways are found in Hawaii, Alaska, and Puerto Rico. The Federal Highway Administration funds four routes in Alaska and three routes in Puerto Rico under the same program as the rest of the Interstate Highway System. However, these routes are not required to meet the same standards as the mainland routes: {{cquote|Highways on the Interstate System in Alaska and Puerto Rico shall be designed in accordance with such geometric and construction standards as are adequate for current and probable future traffic demands and the needs of the locality of the highway. Puerto Rico Puerto Rico signs its Interstate Highways as territorial routes, as the numbers do not match their official Interstate Highway designations. Many of the territory's routes are freeway-standard toll roads. ==See also==