N.M. Stat. § 3-12-1.1
Except as provided in Section 3-12-2 NMSA 1978, members of governing bodies, excluding mayors, of municipalities having a population in excess of ten thousand shall reside in and be elected from single-member districts. If any member of the governing body permanently removes his residence from or maintains no residence in the district from which he was elected, he shall be deemed to have resigned. Once, following every federal decennial census, the governing body of the municipality shall divide the municipality into a number of districts equal to the number of members on the governing body. Such districts shall be compact and contiguous and composed of populations as nearly equal as practicable; provided that the governing body of H class counties and of any municipality having a population of ten thousand or less may provide for single-member districts as provided in this section.
NMS § 3-12-1.1