Land surveyors are trained and licensed to find and mark property lines. As discussed above, they are the ones responsible for physically measuring the lots initially and placing survey pins at the corners. A professional survey is the official record of the location of property lines.
In most cases, a mortgage company or title company will require a survey of a property before approving its purchase. The homeowner can contact these companies for a copy of the survey which will include the property lines.
Surveys are also public records, so homeowners can go to the county or local municipality (or check their websites) to obtain a copy.
Old properties may have what is known as a metes and bounds survey. Using landmarks as a “place of beginning” (POB) along with compass readings and distances, a homeowner can theoretically map out their property lines. The landmarks can be roads, creeks, or even trees. However, this creates a problem if the landmark no longer exists.
If a survey is outdated or vague, a homeowner can hire a surveyor to do a new survey. This will clarify the boundaries and should be registered with the county assessor or recorder. This might also be necessary if an argument over the property lines comes up between neighbors. A title company can deny title insurance to a buyer if there is an ongoing dispute over the property’s borders.
The Property Deed
The deed for the house is another way of finding the property lines for your house. It will include the tax description of the property which details the property lines. If the homeowner does not have a copy of the deed in their records, they can get one from the county recorder’s office for a small fee. Many counties also make copies available online.
The county clerk’s office and local zoning department hold plat maps, which are maps of subdivision developments. It shows the exact dimensions of all of the lots in a neighborhood. Often a plat map is included with all of the other documents presented to a buyer at a real estate closing.
Surveyors drive iron spikes (often pieces of rebar) into the ground to mark property corners. Even these can sink in or be covered as the years go by, but surveyors can find them. A homeowner can do the same if they have a general idea of the property’s dimensions (from a plat map or survey) and a metal detector. These pins might, however, be accidentally moved by construction or utility workers, tree removers, fence builders, or anyone else who digs on the property.
Many municipalities and counties use a Geographical Information System (GIS) to store property line information and make it accessible to the public online. A good place to start is the county assessor’s website. There, homeowners can typically enter their address to find a detailed map of their property and its borders.
There are also paid online apps that use GPS and land parcel records to map out residential property lines. Two common ones are LandGlide and Regrid.
State Land Survey Programs
Missouri and Illinois both have programs that provide some additional information that can help in the search for property lines.
The Missouri Land Survey Index allows people to search for plat maps by county, township, or subdivision name. The Illinois State Geological Survey gives township and parcel number information based on street addresses. This information can then be used on the county level to find plat maps.