State Road 373 (NM 373), also known as West Union Avenue, is a 1.496-mile (2.408 km) state highway on the southern border of Mesilla in Doña Ana County, New Mexico, United States, that connects New Mexico State Road 372 (NM 372) with the southern end of McDowell Road.

NM 373 was truncated to its current eastern terminus on November 2, 1992 in a road exchange agreement with the city of Mesilla.

[1] The entire route is in Mesilla, Doña Ana County.

Media related to New Mexico State Road 373 at Wikimedia Commons