Santa Ana | Lots and Subdivisions

Santa Ana Lot Size and Subdivisions: R1 Lots, Parcel Maps, SB 9 Lot Splits and Small Lots

To subdivide is to divide one lot into two or more lots that can be sold separately. In Santa Ana that takes a map approved under Chapter 34 of the Municipal Code, plus the lot size rules of the zoning district in Chapter 41. This page sets out those sizes, who approves each kind of map, the City's SB 9 lot split rules, its small lot subdivisions, and how state law changes the picture. The Santa Ana overview sums up the guide.

Minimum Lot Sizes by District

Source: Santa Ana Municipal Code, Chapter 41, Sections 41-237, 41-247.6, 41-300, 41-274 and 41-275, 41-356, 41-2102 and 41-2109.

Lot frontage, the length of the lot line along the street, matters as much as area. In R1, Section 41-237 measures it "from the back of the front yard setback," and asks for 50 feet. In R2, a lot with two or more homes needs 75 feet. Section 34-56 adds a subdivision rule that "Every lot must have frontage on a public or private street," with special rules for commercial master sites and condominium projects. A suffix on the zoning map may raise these numbers: under Section 41-185, a number before the district name sets a minimum lot width and a number after it sets a minimum lot area.

Developed apartment sites carry a rule against later division. Section 41-272.05 says that once an R3 site is developed, it shall not "be divided into two (2) or more parcels under separate ownership unless each parcel which would result from such division complies on its own" with R3. Section 41-303 sets a similar rule for R4 and asks for a deed restriction on the open land that lasts "not less than thirty (30) years."

Parcel Maps, Tract Maps and Who Decides

Chapter 34 is enacted under the City Charter and the state Subdivision Map Act, the state law that governs how land is divided (Section 34-1). A tentative map is the first, proposed version of a subdivision; once approved and its conditions are met, the owner records a final map (for a tract) or a parcel map. Section 34-12 names the "advisory agency" for each step: "the zoning administrator for tentative parcel maps; the planning commission for all other tentative maps; and city engineer for all final maps."

Both bodies decide at a public hearing. Under Section 34-126, the Zoning Administrator reviews a tentative parcel map "after Development Project Plan approval" and "At a duly noticed public hearing," and approves it if the design meets Chapter 34. Section 34-127 sets the same process for other tentative maps before the Planning Commission. A subdivider may appeal a Zoning Administrator decision to the Planning Commission within 10 days (Section 34-129), and a Planning Commission decision to the City Council within 10 days (Section 34-132). Each appeal must include "a statement by the subdivider of willingness to extend the time of approval of the map for a period of an additional thirty (30) days."

Parcel maps are "processed and approved by the city engineer in the same manner as final maps" (Section 34-105). When all dedications and improvements are complete, the director of planning "shall waive the requirement that a parcel map be filed" if the findings in Section 34-106 are met. No map may be approved if the result would violate Chapter 8 or Chapter 41, though a tentative map may be approved on condition that the subdivider obtains the needed permits or variances (Section 34-67).

Section 34-81 lists the minimum public works a subdivider must build or agree to build before the City Engineer approves the final map, from street grading, curbs, gutters and sidewalks to water and sewer lines to each lot, fire hydrants, street trees and street lights. Large subdivisions may also owe park land: Section 34-201 applies to a subdivision "containing more than fifty (50) parcels proposed for residential use," and Section 34-204 sets 348.5 square feet per single-family home, 261.4 per duplex home and 209.1 per multifamily home.

The FY 2026-27 Adopted Miscellaneous Fees Schedule sets the costs. Planning charges $6,083 plus $26 per lot to file a tentative parcel map, and $6,558 plus $26 per lot and $26 per home for a tentative tract map. Public Works then charges $9,145 to check a final parcel map, and $8,384 for a final tract map of 5 to 10 lots. A lot line adjustment is $1,800 in Planning and $1,947 in Public Works. The permits and fees page lists the rest.

SB 9 Urban Lot Splits in Santa Ana

An urban lot split is the SB 9 division of one existing lot into two, approved by staff without a hearing under Government Code 66411.7. Santa Ana wrote its version into Division 2 of Article XX by Ordinance NS-3013 of December 21, 2021. It defines the split as "the subdivision of an existing, legally subdivided lot into two (2) lots" (Section 41-2106), and Section 41-2108 says the parcel map "is approved or denied ministerially, by the Executive Director of Planning and Building or their designee, without discretionary review."

Source: Santa Ana Municipal Code, Chapter 41, Article XX, Division 2 (Sections 41-2105 to 41-2110), Supplement 33 Update 1.

The lot must be "in a zoning district that allows single-family residences" and must clear a list of exclusions: farmland, wetlands, very high fire hazard zones, hazardous waste sites, earthquake fault zones and flood zones unless their mitigations are met, and protected habitat (Section 41-2109 (c)). It may not be a historic property or in a historic district, may not have been created by an earlier urban lot split, and may not sit next to a lot that the same owner split under SB 9. The split may not demolish or alter rent-restricted or rent-controlled housing, housing withdrawn from rent under the Ellis Act in the past 15 years, or "Housing that has been occupied by a tenant in the last three (3) years," and the owner must swear to this in an affidavit.

Each new lot is limited to two homes "of any kind," so a lot with two SB 9 homes has no room for an ADU. Each primary home must be "Less than or equal to eight hundred (800)" and "More than five hundred (500) square feet." On a new lot under 2,000 square feet, a new home may be two stories and 22 feet, with the second story set back a further 5 feet. Coverage is 35 percent, or 50 percent if the homes are one story and deed restricted to stay that way, but only "to the extent that it does not prevent two (2) primary dwelling units on the lot at eight hundred (800) square feet each." Front setbacks are 20 feet. Side and rear setbacks follow the zone but give way to allow two 800 square foot homes, never closer than 4 feet to the line.

The City's SB 9 checklist adds practical steps for a split: a Development Project Review application, a subdivision application, drainage to the street or a shared drainage easement, access and utility easements across the new line, and a separate water meter and sewer lateral for each lot.

Where Santa Ana's Split Rules and State Law Differ

Division 2 dates from 2021. Government Code 66411.7 was last amended by SB 1426, effective June 30, 2026. Where the two conflict, the statute controls. Four points need care.

• The affordability deed restriction. Section 41-2109 (n)(4) requires "any net new unit created as a result of the provisions of this division be deed restricted for affordable housing." Government Code 66411.7 sets its own conditions, such as easements, street access and parking, and its text contains no affordability requirement. Ask the Planning Division how it applies this rule today.
• The 800 square foot cap. The statute bars standards that "would result in a unit size of less than 800 square feet." Santa Ana sets 800 as the maximum, so a home on a split lot can be 800 square feet and no larger. Houses on R1 lots that were never split have no such cap.
• Decision deadline. The statute says a split "shall be considered and approved or denied within 60 days" of a complete application, or it "shall be deemed approved." Division 2 sets only a 30-day notice of incompleteness.
• The City's checklist. The checklist says lots "located within a special flood hazard area" do "not qualify," while Section 41-2109 (c)(1)(F) allows them if the FEMA conditions are met. The checklist also cites Government Code 65852.21, the two-unit statute, for lot splits. The code and the statute control over the checklist.

Small Lot Subdivisions

Division 1 of Article XX, adopted in 2018 and amended in 2021, lets a developer create lots for detached houses smaller than the normal minimum. A small lot subdivision is "a residential development containing detached single-family residences or live-work units on land that is subdivided into fee simple parcels containing each unit" (Section 41-2101). Fee simple means each owner owns the land under the home outright, unlike a condominium.

The places are limited. Section 41-2102 permits small lots in "Specific Development No. 84 (Transit Zoning Code), Specific Plan No. 2 (Harbor Mixed Use Transit Corridor Specific Plan), and Metro East Mixed Use Overlay Zone (OZ-1) where single-family and live-work uses are allowed," or through a new SD district. Each lot needs at least 1,000 square feet, not counting shared space, and structures may cover up to 70 percent of it. Each home needs at least 300 square feet of private open space, 15 feet in each direction, which may be on the roof. Projects of 10 or more lots add common open space of at least 5 percent of the site and at least 100 square feet per home.

Other rules shape the design. No minimum separation applies along the new interior lot lines, but each unit must stand on its own lot "with no common foundation, walls or footings." Five or more parcels sharing access need an association, while four or fewer may sign a recorded maintenance agreement instead. Asphalt is not allowed for driveways or parking. The Zoning Administrator may modify these standards through a minor exception (Section 41-2103).

SB 684 and SB 1123 Maps

Government Code 66499.41, the state small-lot map law, requires a city to approve "without discretionary review or a hearing" a map of 10 or fewer parcels for 10 or fewer homes. It applies to a lot "Zoned to allow multifamily residential dwelling use" of up to five acres, or a lot "Vacant and zoned for single-family residential development" of up to one and one-half acres. New parcels must be at least 600 square feet, or 1,200 square feet in a single-family zone, and the homes may average no more than 1,750 net habitable square feet. The version in force on October 9, 2026 was amended by SB 1090, effective September 30, 2026, with changes that start January 1, 2027.

Santa Ana's code has no chapter carrying out this statute, so it applies on its own terms. In Santa Ana it reaches lots where the zone permits multiple-family dwellings, such as R3, R4 and the UN-1 and UN-2 zones of the Transit Zoning Code. Two parts of it interact with local rules. The project "complies with any local inclusionary housing ordinances," which brings in Santa Ana's affordable housing ordinance for projects of five or more homes. And the map may not require demolishing "Housing that is subject to any form of rent or price control" or "Housing occupied by tenants within the five years preceding the date of the application." Santa Ana's rent stabilization ordinance covers many older rental buildings, which the rent and historic homes page explains. The state SB 684 and SB 1123 page covers the statute.

Where to Go Next

Related on VanPlex: the SB 9 page, the SB 684 and SB 1123 page and the Santa Ana overview.

Frequently Asked Questions

Official sources (checked October 2026)