After the Special Committee on Route Numbering initially disapproved the application, the AASHTO Board of Directors approved the I-2 designation, conditional on the concurrence of the Federal Highway Administration.

It remains co-signed with I-69E/US 77 until Harlingen, where I-69E/US 77 makes a sharp turn northward and US 83 maintains a westerly route to McAllen, concurrent with I-2 until Peñitas.

From there, the highway roughly parallels the Rio Grande until Laredo where it makes a northwesterly turn toward Carrizo Springs, the seat of Dimmit County.

After continuing northward through several rural western Texas towns, US 83 then merges with US 84 east of Tuscola, where it makes a sharp turn back to the north.

On March 15, 2022, a bill was signed by President Joe Biden that added the extension of I-27 north to Raton, New Mexico, and south to Laredo to the Interstate Highway System.