What State Is Directly South of Colorado?

No state lies directly south of Colorado. Colorado's southern border runs along the 37°N parallel, meeting:

• New Mexico – to the south-southeast (covers most of the southern border).
• Oklahoma – to the southeast (small corner).
• Arizona – touches only at the Four Corners point (southwest).
• Utah – west.
• Kansas – east.

So New Mexico is the primary southern neighbor, but offset to the east.