Utah Code § 10-20-801
§ 10-20-801. Enactment of subdivision ordinance.
(1) The legislative body of a municipality may enact ordinances requiring that a subdivision plat comply with the provisions of the municipality's ordinances and this part before: (a) the subdivision plat may be filed and recorded in the county recorder's office; and (b) lots may be sold. (2) If the legislative body fails to enact a subdivision ordinance, the municipality may regulate subdivisions only to the extent provided in this part. (3) The joining of a lot or lots to a parcel does not constitute a subdivision as to the parcel or subject the parcel to the municipality's subdivision ordinance. (4) A legislative body may adopt a land use regulation that specifies that combining lots does not require a subdivision plat amendment.