The highway begins in Sunland Park at the Texas state line, just west of the Rio Grande river.

The road travels by residential and commercial areas of the town of Sunland Park, skirting it from the east for the next 4 miles.

Continuing in the general northwest direction, the highway passes Riverside Elementary School at a 4-mile mark.

NM 273 continues north for about 2.6 miles (4.2 km), skirting the fields and pecan orchards of Mesilla Valley from the west, then turns east.

After about one mile, the road turns north, and almost immediately east again, and reaches its northern terminus at intersection with NM 28.