Aerial view looking straight down on three adjoining single-story houses, with hedges and walls along the shared lot lines between their yards, a front lawn, gravel landscaping and palm trees along the street.

Land Development & Mapping

Lot Line Adjustments & Mergers

Move a shared property line or combine lots, with a plat and legal descriptions ready for agency approval and recording.

What is a lot line adjustment?

A lot line adjustment is a city- or county-approved change to the shared lines between four or fewer existing adjoining parcels, moving land from one parcel to another without creating any additional parcels, and recorded by deed.

It is often shortened to LLA and also called a boundary or property line adjustment. Every owner of record usually signs, and lenders with a deed of trust may need to consent.

A lot merger combines two or more contiguous parcels into one, either at the owner's request (a voluntary merger) or by the city or county. Neither can create a new lot; that takes a parcel or subdivision map. Most adjustments start with a boundary survey of the existing lines.

What's included in a lot line adjustment

Scope is set for each project in the proposal. A typical adjustment or merger package covers:

  • Boundary survey

    Existing corners, lines and record evidence located before any line moves.

  • Record research

    Vesting deeds, recorded maps, easements and deeds of trust reviewed for each parcel.

  • Adjustment plat

    Existing and proposed lines, areas, bearings, distances and easements on one exhibit.

  • Legal descriptions

    Signed and sealed descriptions of each adjusted parcel and each transferred strip.

  • Setback exhibit

    Buildings, septic systems and wells shown with their distances to the proposed line.

  • Merger documents

    A merged-parcel description and exhibit, or a parcel map for a reversion to acreage.

  • Agency coordination

    Plan-check comments from the planning department or county surveyor answered and resubmitted.

  • Monuments & filings

    New corners set where the scope calls for them, and any required record of survey.

When do you need a lot line adjustment?

Most adjustments fix a line that no longer fits how the land is used.

  • Fixing a building or fence encroachment

    Move the line so a garage, fence or driveway sits on its owner's land.

  • Buying a strip from a neighbor

    Add yard, parking or access area to your parcel.

  • Meeting setbacks for an addition or ADU

    Reshape lots so a planned accessory dwelling unit (ADU), pool or septic system meets setbacks. See site layout.

  • Combining lots you own

    Merge contiguous parcels you own so one project can use the whole site.

  • Improving access or frontage

    Give each parcel usable access to a street or a recorded easement. See legal descriptions and easements.

  • Preparing land for sale or development

    Straighten odd shapes or lines before a sale, a refinance, or a parcel map.

How a lot line adjustment works

Five steps from first review to recorded deeds.

  1. Research the parcels

    Title reports, deeds and recorded maps show how each parcel was created and who signs; the agency may ask for proof of legal lot status, such as a certificate of compliance.

  2. Survey the existing lines

    A boundary survey recovers existing corners and locates buildings, septic systems, wells and driveways near the proposed line.

  3. Prepare the package

    The plat, legal descriptions and exhibits are drafted to the agency's checklist and zoning setbacks, then signed and sealed by the licensee in responsible charge.

  4. Agency review

    The planning department, city engineer or county surveyor checks zoning conformity and technical accuracy before approval.

  5. Record and monument

    Deeds reflecting the adjustment are recorded, along with any approval document the agency requires. Any new corners are set, with a record of survey filed when state law requires one.

California requirements for lot line adjustments

The Subdivision Map Act and the Professional Land Surveyors' Act set the statewide rules:

  • Gov. Code §66412(d)

    Four or fewer parcels, limited review

    The city or county reviews only whether the resulting parcels conform to its general plan, any specific or coastal plan, and zoning and building ordinances. Conditions are limited to that conformity, prepaying property taxes, and relocating existing utilities, infrastructure or easements.

  • Bus. & Prof. Code §8762

    Recorded by deed, not by map

    No tentative, parcel or final map is required (Gov. Code §66412(d)); the adjustment is reflected in a recorded deed. A record of survey is needed only when §8762 requires one, and it is then filed with the county surveyor within 90 days of setting boundary monuments or completing the field survey, whichever comes first (§8762(c)).

  • Bus. & Prof. Code §8726, §8761

    Descriptions by a licensed surveyor

    Describing property limits in a deed is land surveying (§8726(a)⁠(12)). New descriptions must be prepared by, or under the responsible charge of, a licensed land surveyor or a civil engineer authorized to practice land surveying, then signed and sealed (§8761).

  • Gov. Code §66451.10, 66499.20.3

    Mergers by the agency or the owner

    Parcels do not merge just because one owner holds them (§66451.10). An agency-initiated merger needs a merger ordinance, a parcel below minimum lot size, other §66451.11 conditions such as an undeveloped parcel, and notice with a chance for a hearing. Where an ordinance allows, owners can merge contiguous parcels they own by recorded instrument (§66499.20.3), or revert up to four such parcels to acreage with a parcel map (§66499.20.1).

Requirements vary by city and county: the reviewing office, submittal list, fees and approval life are set locally, and coastal-zone parcels may need extra review.

Sources & references
  1. Government Code §66412, lot line adjustments (California Legislative Information)
  2. Government Code §66451.11, merger of parcels by a city or county (California Legislative Information)
  3. Government Code §66499.20.3, voluntary merger of contiguous parcels (California Legislative Information)
  4. Business and Professions Code §8762, when a record of survey must be filed (California Legislative Information)
  5. Business and Professions Code §8726, practice of land surveying, including legal descriptions (California Legislative Information)

Last reviewed .

Lot line adjustment FAQs

What is the difference between a lot line adjustment and a lot merger?

A lot line adjustment moves lines between existing adjoining parcels without adding parcels (Gov. Code §66412(d)). A lot merger turns contiguous parcels into one parcel, either at the owner's request where a local ordinance allows it (§66499.20.3) or by the city or county under a merger ordinance (§66451.11).

Can a lot line adjustment create a new buildable lot?

A lot line adjustment cannot create a new lot. California law limits it to moving lines among existing adjoining parcels without increasing their number (Gov. Code §66412(d)). An additional lot requires a parcel map, or a tentative and final map, under the Subdivision Map Act.

Who can prepare lot line adjustment documents in California?

Lot line adjustment plats and legal descriptions are land surveying in California (Bus. & Prof. Code §8726(a)⁠(3), (a)⁠(7), (a)⁠(12)). A licensed land surveyor, or a civil engineer authorized to practice land surveying, must prepare them or be in responsible charge, then sign and seal them (§8761). Only civil engineers registered before January 1, 1982 have that authority without a land surveyor license (§§6731, 8731).

Does a lot line adjustment require a survey or a record of survey?

A lot line adjustment often starts with a boundary survey, and many agencies require a plat by a licensed surveyor. A record of survey is required only when Business and Professions Code §8762 applies (Gov. Code §66412(d)), such as when new corners are set at points no recorded map shows.

Does a lot line adjustment change property taxes?

A lot line adjustment can change property taxes when land moves between different owners. Revenue and Taxation Code §65.1 limits reappraisal to the portion that changes ownership. State Board of Equalization Property Tax Annotation 220.0396 says an adjustment between parcels owned by the same people is not a change in ownership. The county assessor decides each case.

What affects the cost and schedule of a lot line adjustment?

The cost and schedule of a lot line adjustment depend on the number of parcels and owners, the condition of monuments and records, each parcel's legal status, structures near the new line, lender consents, and the agency's review path and fees. Share the parcel numbers, a title report or vesting deeds, and a sketch of the new line; the proposal then sets scope and timing.

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Lot Line Adjustments & Mergers

Need a lot line adjustment in California?

Send the parcel numbers, a title report or vesting deeds, and a sketch of the line you want. We'll confirm the approval path and scope before fieldwork.