To determine the lot lines on your property, work from the paperwork outward: read the legal description in your deed, pull the recorded plat map for your subdivision, walk the ground looking for the iron pins or monuments a surveyor placed at the corners, and cross-check what you find against your county’s online GIS map. Each source tells you something slightly different, and none of them is as authoritative as a new survey by a licensed land surveyor. For most homeowners, the documents and markers are enough to get oriented; when money, construction, or a neighbor dispute is on the table, a professional survey is the only answer that holds up.
Start With Your Deed and Plat Map
Your deed is the legal document that transferred ownership to you, and it contains a legal description of the parcel.1Legal Information Institute. Deed That description uses one of two systems. A metes and bounds description traces the perimeter with compass bearings, distances, and reference points, starting and closing at the same spot. A lot and block description, common in subdivisions, identifies your parcel by lot number, block number, and the name of the recorded subdivision. You can request a copy from the county recorder’s or clerk’s office where the property sits.
A plat map is the companion document. Where the deed describes a single parcel, the plat shows the full subdivision layout: individual lots, streets, block numbers, dimensions, and often easements and utility corridors. Plats are prepared by licensed surveyors and recorded with the county, so the recorder’s office or its website is where to look. Focus on the measurements, compass bearings, and reference points; those numbers are the bridge between the description on paper and the ground under your feet.
Find the Physical Corner Markers
Most surveyed lots have physical markers at the corners. They are usually iron rods or rebar two to three feet long, sometimes capped with colored plastic. Older properties may have stone markers, concrete monuments, or hollow iron pipes. Surveyors set them at corner points and occasionally along long runs between corners.
Bring your plat map and a tape measure. Front markers are usually easiest to find because they sit near sidewalks or the road, often six to ten inches below the surface. Measure from a known front marker toward where the plat says your rear corners should be. A basic metal detector helps when markers are buried under years of grass and soil. Before you dig, call 811 so underground utilities are marked; you do not want to hit a gas line while hunting for an iron pin.
One caution. Existing fences, hedgerows, and driveways often do not sit on the actual line. A previous owner may have built the fence two feet inside their boundary, or a neighbor’s fence may have crept the other way. A marker placed by a surveyor is far more trustworthy than any fence or landscaping feature.
Check the County GIS Map
Most counties publish Geographic Information System (GIS) maps through the assessor’s or planning department website. These tools overlay parcel boundaries onto aerial imagery and let you search by address or parcel number to see approximate lot dimensions, neighboring parcels, and sometimes easements and flood zones.
GIS is useful for getting oriented, but it is not legally definitive. The lines you see are digitized from recorded plats and deeds, and the process of layering them onto aerial photos introduces error. In older neighborhoods and rural areas where original surveys were less precise, GIS lines can be off by several feet. Use these maps as a visual reference, not as the basis for building a fence or pouring a foundation.
Hire a Licensed Land Surveyor
When the answer has to be legally binding, hire a licensed land surveyor. That means before you build an addition, install a fence along a disputed line, buy or sell property, subdivide land, or respond to a neighbor’s encroachment claim. Skipping a survey before construction is where most boundary problems start, because by the time the mistake is discovered, the concrete is already poured.
What a Surveyor Actually Does
A surveyor starts with records research, pulling your deed, neighboring deeds, prior surveys, and the recorded plat. That research often takes more time than the fieldwork, especially with old or incomplete records. In the field, the surveyor uses high-precision GPS receivers and total stations to measure the parcel, locates existing markers, and sets new ones where originals are missing. The deliverable is a certified survey plat showing exact boundary lines, dimensions, corner marker locations, and any encroachments or easements found.
What a Survey Costs
A standard residential boundary survey typically runs between $1,200 and $5,500 nationally. Price depends on property size, lot shape, terrain, and how much time the surveyor spends on historical records. Urban lots with clean platting and nearby reference points fall toward the lower end. Large, irregular, or heavily wooded rural parcels push costs up. If records conflict or extra documentation is needed, research alone can add several hundred dollars.
Every state licenses land surveyors, and the state licensing board maintains a searchable roster of active licensees. Searching your state name plus “licensed land surveyor roster” gets you there. Get quotes from at least two or three firms, and ask whether the estimate includes records research, marker placement, and the final certified plat. A quote that looks unusually cheap may not include all three.
ALTA/NSPS Surveys for Commercial Transactions
If you are buying commercial property or a lender requires it, you may need an ALTA/NSPS Land Title Survey rather than a standard boundary survey. These follow national standards set jointly by the American Land Title Association and the National Society of Professional Surveyors and include enough detail for a title insurance company to remove the general survey exception from its policy. The 2026 standards, effective February 23, 2026, explicitly accommodate drones and LiDAR alongside traditional methods.2National Society of Professional Surveyors. 2026 ALTA/NSPS Standards ALTA surveys often run $2,000 to $3,000 or more because the scope and documentation are much greater.
Setbacks and Easements Limit What You Can Do Near the Line
Knowing where the line falls is only half the picture. What you can build near it is governed by setbacks and easements, and both can surprise you.
A setback is the minimum distance your local zoning code requires between a structure and a property line. Most residential zones impose front, side, and rear setbacks, and they differ. A typical front setback might be 20 to 30 feet, while side setbacks may be as little as 3 to 5 feet. The exact numbers depend on your zoning district, so check with the local planning or building department before planning construction. Building inside a setback without a variance can trigger a stop-work order or a demolition requirement.
An easement gives someone other than you a legal right to use part of your property for a specific purpose. The most common is a utility easement, which lets a power, water, or telecommunications provider install and maintain lines through your yard. You still own the land, but you generally cannot put permanent structures on it. A negative easement can prevent you from doing something otherwise legal on your own land, such as constructing a building that blocks a neighbor’s view or light.3Legal Information Institute. Easement Easements are usually recorded with your deed or on the plat map, so pull both documents and look for them.
When the Deed and a Survey Disagree
This happens more often than people expect, especially with older properties. Your deed might call the lot 150 feet deep, and a surveyor measures 147. Or the deed calls for a boundary along a stone wall that was moved decades ago. Courts follow an established priority when these conflicts arise.
Physical monuments on the ground generally beat written measurements in the deed. A reference to a specific survey carries the most weight. Then natural monuments like rivers and ridgelines, then artificial monuments like iron pins, concrete markers, and recorded boundaries of neighboring parcels, and only then compass directions and distances. Acreage stated in a deed (“approximately 0.5 acres”) is the weakest indicator and almost always yields to boundary calls and measurements. Where the intent expressed in the deed clearly contradicts the ranking, courts may let intent control, but that is the exception.
The practical point: if your deed says one thing and a new survey says another, the survey usually reflects reality more accurately. A title attorney can help sort out the legal implications, especially if the discrepancy touches a neighbor’s land.
Protect the Line Once You Know Where It Is
Two legal doctrines make it worth acting on what a survey shows rather than filing it away.
Encroachment is when a structure, fence, driveway, or landscaping feature crosses onto a neighbor’s property. Minor drifts of a few inches usually resolve through a conversation. Larger ones, like a garage or retaining wall sitting partly on someone else’s land, typically require legal action. The affected owner can seek a court order requiring removal, negotiate a formal easement, or sell the encroached strip. The longer an encroachment sits, the harder it gets to unwind.
Adverse possession is the doctrine that lets someone openly using part of your land eventually claim legal ownership of it. Required time periods vary widely by state, from as few as five years to as many as twenty-one, depending on the jurisdiction and whether the possessor holds color of title.4Legal Information Institute. Adverse Possession The possession has to be open, hostile (meaning without your permission), actual and exclusive, and continuous for the full statutory period. The word that matters most is hostile. Written permission converts a neighbor’s use from hostile to permissive, and the clock for adverse possession never starts. If you know a neighbor is using a strip of your land and you are fine with it, a short written license protects your ownership.