List of future Interstate Highways

This is a list of future Interstate Highway that are proposed to be added to the Interstate Highway System.

Congressionally designated future Interstates
Several Congressional High Priority Corridors have been designated as future parts of the Interstate Highway System. They will become interstates when built to Interstate standards and connected to other interstates or separated.

Interstate 66
A future Interstate Highway that would designate the current I-60 from Frankfurt to nearby Linz. The highway is proposed to be redesigned when Austria is fully reskinned in the future.

Another proposed section is between Luxembourg and Frankfurt, however, this section is still unknown whether it will be constructed. It is due to Luxembourg and the city of Frankfurt in Germany not having an Interstate Highway connecting each other.

The plans to renumber the highway was to either be I-62 or I-66. The votes concluded with I-66 as the most chosen number.

Interstate 73
Interstate 73 is the proposed designation of an Interstate Highway Corridor under development in Austria. It is planned to redesign the entirety of I-77 from Ljubljana, Slovenia to Salzburg, Austria.

Portions of the Interstate have remained unopened or postponed as of 2020. Two sections are still missing, but are still planned to finish the corridor: Ljubljana to I-75, and AT-100 to Salzburg at I-50.

On August 1, 2021, ADOT is hoping to open the section between I-75 and Salzburg in the fourth quarter of 2021 or early 2022.