N.M. Stat. § 47-1-49
The system of plane coordinates which has been established by the national ocean survey and national geodetic survey for defining and stating the positions or locations of points on the surface of the earth within the state of New Mexico shall be known and designated as the "New Mexico coordinate system". As used in Section 47-1-49 through 47-1-56 NMSA 1978, the term "New Mexico coordinate system" includes both the New Mexico coordinate system of 1927 and the New Mexico coordinate system of 1983.
For the purpose of the use of this system, the state is divided into an "east zone", "central zone" and a "west zone".
The area now included in the following counties shall constitute the east zone: Chaves, Colfax, Curry, DeBaca, Eddy, Guadalupe, Harding, Lea, Mora, Quay, Roosevelt, San Miguel and Union.
The area now included in the following counties shall constitute the central zone: Bernalillo, Dona Ana, Lincoln, Otero, Rio Arriba, Sandoval, Santa Fe, Los Alamos, Socorro, Taos, Torrance and Valencia.
The area now included in the following counties shall constitute the west zone: Catron, Cibola, Grant, Hidalgo, Luna, McKinley, San Juan and Sierra.
NMS § 47-1-49