Land Surveying
Boundary Surveying
Know where your property lines and corners are on the ground before you build, fence, buy, or divide land.
What is a boundary survey?
A boundary survey is a land survey that locates or retraces a parcel's property lines and corners from deeds, recorded maps, and monuments found in the field, then shows them on a signed and sealed map and can mark missing corners with new monuments.
Often called a property survey, property line survey, or lot survey, it shows where your land ends, where a neighbor's begins, and where recorded easements cross it. Buyers, lenders, and title officers use it to confirm what is being conveyed.
It maps lines and corners, not the shape of the ground, so design projects pair it with a topographic survey on the same survey control. A boundary survey cannot move a line or confirm that a parcel was legally created; that takes a lot line adjustment or a certificate of compliance from the city or county.
Deliverables
What's included in a boundary survey
Scope is set for each parcel in the contract. A boundary survey typically includes:
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Boundary map
A signed and sealed map with bearings, distances, basis of bearings, and adjoining lines.
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Corner monuments
Corners found, set, or reset; each new monument is tagged with the licensee's number.
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Record research
Deeds, recorded maps, records of survey, and corner records for your parcel and neighbors.
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Easements plotted
Recorded easements located from their descriptions, typically from a preliminary title report you provide.
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Nearby improvements
Fences, walls, buildings, and driveways near the lines, with potential encroachments noted.
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County filing
A record of survey or corner record filed with the county surveyor when required.
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Survey control
Control points and a stated basis of bearings, reusable for topographic mapping and staking.
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Digital files
A signed PDF, a CAD file (typically DWG), and coordinates for corners and control.
When do you need a boundary survey?
Order one before you design, build, fence, or sign.
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Building near a property line
Additions and accessory dwelling units (ADUs) near a setback are placed from surveyed lines. See site layout plans.
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Building or replacing a fence
Build from the surveyed line, not an old fence: just inside it, or on it by agreement with your neighbor.
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Buying a lot or parcel
Confirm what you are buying and see easements and potential encroachments before closing.
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Settling a line question with a neighbor
A sealed map gives both owners, and their attorneys, the same evidence.
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Adjusting, merging, or dividing lots
New lines start from the existing boundary, so the survey comes first. See lot line adjustments.
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Writing an easement or deed description
New legal descriptions and easements are tied to surveyed corners, not assessor maps.
On commercial deals, lenders and title insurers usually ask for an ALTA/NSPS land title survey, a national standard whose 2026 edition took effect February 23, 2026.
Process
How a boundary survey works
What happens after you call, step by step.
Define the purpose
We confirm the survey's purpose and which corners matter, then set scope and fees in a written contract (Bus. & Prof. Code §8759).
Research the records
We gather deeds, recorded maps, records of survey, corner records, and the title report for your parcel and its neighbors.
Search for monuments
Crews search your corners and adjoining lines for monuments, typically measuring with GNSS (satellite positioning) receivers and total stations.
Analyze the evidence
The licensee in responsible charge compares found monuments with the record and decides where the lines and corners belong.
Set corners and map
When in scope, missing corners get tagged monuments; the sealed map shows lines, monuments, easements, and improvements.
File with the county
When state law requires, a record of survey or corner record goes to the county surveyor, who examines it before it is filed.
California rules
California requirements for boundary surveys
Boundary surveying is licensed work. The rules that matter most:
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Bus. & Prof. Code §8726, §8731
Licensed land surveyors do boundary work
Locating or retracing property lines and setting corner monuments are land surveying (§8726), reserved for licensed land surveyors and civil engineers registered before January 1, 1982 (§8731). The licensee in responsible charge signs and seals the map (§8761).
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Bus. & Prof. Code §8762(b)
When a record of survey is required
A record of survey must be filed with the county surveyor when the field survey finds evidence or physical changes not shown on any recorded map, a material discrepancy with recorded maps, or evidence that could lead to materially different line positions, or when it establishes or sets points or lines no recorded map shows.
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Bus. & Prof. Code §8762(c), §8765(d)
Deadline, or a corner record instead
A required record of survey is due within 90 days after boundary monuments are set or the field survey is completed, whichever comes first (§8762(c)). A retracement that matches the recorded map and finds enough monuments needs only a corner record for any corners set, reset, or found different from the record (§8765(d)).
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Civ. Code §841
Neighbors share boundaries and fences
Adjoining owners share equally in maintaining the boundaries and monuments between them and are presumed equally responsible for the reasonable cost of a dividing fence. An owner who intends to incur costs for one must first give each affected adjoining owner 30 days' written notice of the problem, proposed fix, estimated cost, and cost split (Civil Code §841).
Requirements vary by city and county; ask your building department early whether your permit needs a boundary survey.
Sources & references
- Business and Professions Code §8731, civil engineers and the 1982 land surveying rule (California Legislative Information)
- Business and Professions Code §8762, when a record of survey is required (California Legislative Information)
- Business and Professions Code §8765, retracement surveys and corner records (California Legislative Information)
- Business and Professions Code §8774, surveyor right of entry (California Legislative Information)
- Civil Code §841, boundaries, monuments, and dividing fences (California Legislative Information)
Last reviewed .
Boundary survey FAQs
Who can do a boundary survey in California?
A boundary survey in California must be performed by, or under the responsible charge of, a licensed land surveyor or a civil engineer registered before January 1, 1982 (Business and Professions Code §8731). Civil engineers licensed after that date need a separate land surveyor license for boundary work, although they may do topographic mapping and construction staking.
How can I find my property lines in California?
Property lines in California are described in your deed and often on a recorded subdivision or parcel map; a record of survey or corner record may also be on file with the county. Assessor's parcel maps and online parcel layers are not surveys, and a fence may not sit on the line. Locating the lines on the ground takes a boundary survey.
Does a boundary survey show easements and encroachments?
A boundary survey shows recorded easements that can be located from their written descriptions, usually those listed in a preliminary title report the owner provides. The map also shows fences, walls, and buildings near the lines, so potential encroachments are visible. Whether one is legally an encroachment is for the owners and their attorneys to resolve.
Can a surveyor go onto my neighbor's property?
A licensed land surveyor may enter neighboring property to look for boundary evidence, since monuments that control your lines may sit on adjoining lots. Owners and tenants must allow reasonable access without undue delay (Business and Professions Code §8774; Civil Code §846.5). Prior notice is not required, but they must be told the proposed time of entry where practicable.
What affects the cost and schedule of a boundary survey?
The cost and schedule of a boundary survey depend on the parcel's size and shape, how many corners must be found or set, the quality of the deeds and recorded maps, whether original monuments survive, terrain and access, and whether a record of survey must be filed. Share the address or parcel number, your deed or title report, and why you need the survey; the proposal then sets scope and timing.