Combining Subdivided Lots: What You Need to Know


In San Diego County, there are many new building opportunities for investors and homeowners alike. We are seeing many urban renewal projects in the heart of Downtown San Diego, as well as new development throughout the county, including La Jolla. You have a big dream for a brand new project, either a business, a multi-unit dwelling, or your new luxury dream home. One of the first things you’ll need to do, however, is to check the zoning laws for the land you want through City Hall or the County Assessor’s Office.

The main consideration is that California has long been regulated by the Subdivision Map Act. This means that you can’t divide or combine land in California for sale, lease, or financing without getting approval from your local jurisdiction. This also governs the rezoning of property to take over previously divided spaces. While this can be inconvenient, the purpose of this act is to prevent fraud and exploitation while protecting public health and safety from overcrowding or building on unsafe (toxic/over fault lines) land, to regulate design of improvements and the division of real property, and to protect public and private property interests. In most cases, unless you are a developer taking over a large swath of public land, you should be able to get the property rezoned without going through too many hoops.

There’s also a good chance you may only need to apply for a lot line adjustment. The lot line adjustment allows owners of real property to change ownership boundaries between lots of adjoining owners or multiple parcels under a single ownership. This is not a subdivision of land and so these adjustments are exempt from the Subdivision Map Act. To apply, you can choose either a Lot Line Adjustment Plat (an unrecorded map of the requested boundary adjustment) or a Parcel Map (superior to the plat and may be prepared from record information) to make your adjustment. The plat needs to show all existing lots or parcels as well as the new proposed lines. Keep in mind you will also need a Coastal Development Permit if the parcels to be adjusted fall under the Coastal Overlay Zone.

You’ll have to fill out a General Application Package and pay the processing fees, and provide a title report with associated reference documents. A lot line adjustment or consolidation can’t increase development rights, however, unless additional approval is obtained.

You will be eligible for a lot adjustment if:

• You’re only adjusting four or fewer existing (adjoining) parcels in which land taken from one parcel is added to an adjoining parcel;

• A greater number of parcels than originally existed is not created;

• All the proposed lots for adjustment are legal, buildable lots;

• Lot consolidation is limited to the adjustment or consolidation of four or fewer adjoining lots or parcels into three or fewer parcels.

Fortunately, no public hearing is required for a lot line adjustment, as they are decided by city staff, who will determine whether the application meets the eligibility requirements and satisfies current zoning and building regulations. Upon approval, a land surveyor may prepare and submit the final lot line adjustment plat with legal descriptions OR the parcel map for technical review. City staff will then review the final documents and identify any encumbrances (such as easements, trust deeds that require adjustment to convey a clear title, tax liens, etc.).

There are not many reasons to deny combining properties, unless the city requires the maximum density for that area, which is more likely to occur in the city center than in the suburbs. Also, combinations or mergers deemed to be haphazard might be denied—for example, if two properties are to be combined, the next property skipped over, and then two or more combined on the other side of that. Basically, you probably would not be able to turn an entire block in the city into a single-family dwelling.

For a comprehensive list of all the codes and regulations of San Diego, visit

And for more information on combining lots or building your luxury dream home, multi-unit dwelling, or business, contact us at