The Interstate heads eastward as a four-lane freeway through the Lower Rio Grande Valley.

Approved by the American Association of State Highway and Transportation Officials at their May meeting, this 47-mile-long (76 km) freeway was already constructed as an Interstate-grade limited-access facility.

[9] This action finalized the designations of not only I-2 but also of the sections of I-69E from Brownsville to Raymondville, I-69C from Pharr north to the end of the US 281 freeway facility near Edinburg, and also I-369 along a short segment of US 59 freeway west of Texarkana, which will be part of the proposed 115-mile (185 km) connector between the main I-69 trunk in Tenaha and Texarkana.

[8] These approvals added over 100 miles (160 km) to the Interstate Highway System in the Rio Grande Valley.

[11] As of January 2024[update], the cluster consisting of the recently designated portions of I-2, I-69C, and I-69E in the Rio Grande Valley is not connected to the national Interstate network.

Environmental Protection Agency approval for the expansion of the US 77 alignment to Interstate standards, including bypasses of the towns along the 91-mile (146 km) routing, was obtained through a Finding of No Significant Impact statement issued on July 13, 2012;[12] Due to increasing congestion, a nine-mile (14 km) segment of future I-2 bypassing La Joya were constructed in three phases.

Two of the phases of the segment from west of Palmview to east of Sullivan City were estimated cost $183 million according to TxDOT.

The study, which included collecting and analyzing date and requesting public feedback, began in April 2022 and was completed in August 2023.