I-35E travels north for 97 miles (156 km), maintaining I-35's sequence of exit numbers.

In the case of I-35 in the Dallas–Fort Worth area, since neither branch is clearly the main route and both branches return to a unified Interstate beyond the cities of Dallas and Fort Worth, the American Association of State Highway and Transportation Officials has allowed the suffixes of E and W in Texas to remain in the present day.

[citation needed] From Waco, Texas, to El Dorado, Kansas, I-35 (or I-35E) typically runs concurrent with or lies fairly close to US 77.

This highway travels parallel to I-35E after splitting off of I-35 north of Hillsboro, running through Italy and Milford.

It rejoins the Interstate just north of a junction with State Highway 342 (SH 342) in Red Oak.

[citation needed] From the Dallas–Ellis county line to Downtown Dallas, I-35E is called South R.L.