While numbered as loop routes for I-94, routes I-494 and I-694 in Minneapolis/St. Paul serve as loops for I-35 as well.
- Dallas, Texas - I-635
- Oklahoma City, Oklahoma - I-235
- Wichita, Kansas - I-235
- Spur to Wichita, Kansas and Salina, Kansas - I-135 (see below)
- Spur to Topeka, Kansas - I-335
- Kansas City, Missouri - I-435, I-635
- Des Moines, Iowa - I-235
- Duluth, Minnesota - I-535
A spur has been proposed extending from I-380 in Cedar Rapids, Iowa to St. Paul.
- I-35 splits up into I-35W and I-35E in the Dallas/Fort Worth, Texas area. The official mile markers follow I-35E through Dallas -- I-35W carries its own milage from Hillsboro to Denton, as though it were an x35 loop.
- I-135, which branches off in Wichita, Kansas, is 95 miles long. It carried the designation I-35W until the 1980s, despite never rejoining the main line of I-35. It terminates in Salina, Kansas at the intersection with Interstate 70 (though the controlled-access freeway continues north as US 81).
- I-35 and I-335 in Kansas are toll roads.
- I-35 splits again into I-35W and I-35E in the Minneapolis/St Paul, Minnesota area.