CA SB1123

Expands ministerial subdivision approval to include vacant lots zoned for single-family residential development (up to 1.5 acres) in addition to existing multifamily-zoned lots (up to 5 acres), allowing local agencies to approve applications without discretionary review within 60 days.

Increases minimum parcel size to 1,200 square feet for single-family residential zoned parcels (from 600 square feet) and allows local agencies to impose height limits on vacant single-family lots that are at least equal to existing zoning designations.

Reduces density requirement for parcels not identified in housing elements from "at least as many units" to "at least 66 percent of maximum allowable residential density or applicable density whichever is greater."

Excludes accessory dwelling units and junior accessory dwelling units from counting toward the 10-unit residential limit if local agencies choose to permit them, and adds tenancy in common arrangements as an eligible ownership structure.

Removes frontage requirements and specifies that proposed subdivisions cannot result in existing dwelling units being alienable separate from title to other existing units on the lot; provisions become operative July 1, 2025.