Utah Code § 10-20-602
§ 10-20-602. Limit on single family designation.
(1) As used in this section, "single-family limit" means the number of individuals allowed to occupy each residential unit that is recognized by a land use authority in a zone permitting occupancy by a single family. (2) A municipality may not adopt a single-family limit that is less than: (a) three, if the municipality has within its boundary: (i) a state university; or (ii) a private university with a student population of at least 20,000; or (b) four, for each other municipality.