Legal Descriptions of Real Estate

Sales contracts, deeds, mortgages, and deeds of trust require a legal description of property that is legally sufficient to be binding, meaning that the description would allow a competent surveyor to delineate the exact boundaries of the property. The legal description of a property does not include the buildings on it — only the boundaries of the property. The legal description is also an important determinant in setting the property's price. Although the address is necessary to locate the property, it is not sufficient to identify the property. Indeed, addresses are often renamed over time and even physical boundaries can change course, such as that of a local creek. Note that because any property is necessarily limited in area, any description of that property must necessarily form an enclosed area.

Legal descriptions are generally prepared by a licensed surveyor, who is trained and authorized to locate and determine the legal description of any property. Only a licensed surveyor should prepare property descriptions, since inaccuracies can cause title problems later. The surveyor prepares 2 documents: a survey that gives the property's description and a survey sketch that shows the location and dimensions of the parcel. If the location, size, and shape of buildings on the lot are also given, then it is called a spot survey.

Today, the accuracy of property descriptions is greatly enhanced using computers, satellites, lasers, and global positioning systems (GPS). The Federal Bureau of Land Management and the USDA Forest Service are developing a National Integrated Land System (NILS), using common methods nationwide based on new technology and software to record the survey data and other information for land records.

Legal descriptions always note the county and state in which the property is located. There are 3 independent methods that can be used to determine the exact location and boundaries of a parcel of land:

  1. metes and bounds
  2. rectangular survey
  3. lot and block.

Metes and Bounds System

Metes-and-bounds descriptions were used in the original 13 colonies before the rectangular survey system was developed. A metes-and-bounds description uses lengths and angles of boundaries starting at the point of beginning (POB). A mete is a boundary line and bounds is the area enclosed by the metes — hence, the name. Starting at the POB, the length of each boundary is described and the angle that it forms with the previous boundary. This continues to the point of end (POE), which is identical to the point of beginning, since all properties must have enclosed boundaries.

Of course, for a metes and bounds description to be legally sufficient, the location of the POB must be specified, and is usually specified by a monument (aka landmark), which can be a large artificial or natural object or other stable structure, including rocks, trees, streams, railroads, roads, and intersections that are recorded by surveyors to locate property. Nowadays, many monuments are iron pins or concrete posts installed by surveyors or by the U.S. Corp of Engineers. The actual placement of the monuments is more important than the lengths and angles specified in the legal description, since the measured lengths and angles have meaning only in reference to the monuments and, additionally, marking the beginning and the end with a monument guarantees that the area will be closed.

Tier-and-Range System

The rectangular survey system (aka tier-and-range system, government survey system), was specified by Congress in 1785 to mark large tracts of land that the United States received in its early years, including the Northwest Territory.

The rectangular survey system specifies locations by using a rectangular coordinate system — hence, the name — that consists of principal meridians that run north and south and identifiable by longitude, and base lines that run east and west, identifiable by latitude. Principal meridians and base lines partition the land into quadrangles, which are squares of land with each side measuring 24 miles. These quadrangles are further subdivided in 16 townships, with each side of a township measuring 6 miles and covering an area of 36 square miles. Townships are further subdivided into 36 1-square mile sections, with each section equal to 640 acres. In many states, the rectangular survey system is supplemented with a mete-and-bounds description to describe small parcels of land.
The rectangular survey system, illustrating the formation of the quadrangle with the meridian and base line, and further subdivided into townships, which are subdivided further in sections of 640 acres each,

Correction Lines

Because the Earth is an oblate spheroid, range lines are not exactly 6 miles apart along the entire length, since they must ultimately converge to the same point at the North Pole. Correction lines are used to account for the fact that a township's north boundary will be slightly shorter than its south boundary.

A correction line is every 4th township line — a distance of 24 miles — and guide meridians, which run north and south at 24 mile intervals from the principal meridian and are exactly parallel to the principal meridian, so that the discrepancy in area bounded by the correction lines and guide meridians — known as a government check — can be compared to the actual area bounded by the regular meridians, so that the discrepancy can be accounted for by reducing the size of the townships in the north and west of a quadrant.

Sections adjacent to the north and west boundaries of the township are adjusted according to well-established rules, using the difference between the government check and the actual area. The adjusted sections are called fractional sections, because they are slightly less than 1 square mile, but the remaining sections in a township are standard sections, each exactly 1 square mile.

Fractional Sections and Government Lots

Fractional sections that are more or less than 1 square mile also arises for reasons other than the fact that the meridians are not exactly parallel, which often occurs because the rectangular survey was done by separate crews working independently, resulting in gaps of less than 6 miles between the different surveyed areas. Fractional sections can also be caused by physical difficulties in surveying the land, because, for instance, some of it was submerged in water or because a township boundary was circumscribed by a state boundary line. Areas smaller than full quarter sections of 160 acres are called government lots.

Lot-and-Block System

The other system of legal description is the lot-and-block system (aka recorded plat system), which refers to specific parcels of land identified by a lot number or letter and the block, or subdivision plat, in which the lot is located. The block itself is located by using either the metes and bounds system or the rectangular survey system. To identify a particular parcel of land, the lot-and-block system specifies the lot and block number, the name or number of the subdivision plat, and the name of the county and state.

Measuring Elevations

Some property may have descriptions involving elevations. Elevations must also be used for so-called air lots or subsurface rights. For instance, condominiums located on upper floors or lower floors may be described in reference to a datum, which is a point, line, or surface from which elevations are measured. The United States Geological Survey (USGS) references a datum that is defined as the mean sea level at New York Harbor.

Although monuments are frequently used as reference points for a datum, their location can easily be altered either by the force of nature or through vandalism. Therefore, surveyors generally use benchmarks, which are permanent reference points of brass markers set in solid concrete or an asphalt base that are used principally for marking a datum. All large cities have their own official local datum for easier reference by their surveyors.


Measurements are a necessary part of any legal description. Old measurements were based on chains and rods because surveyors at that time used these to measure distances. The following list shows the relationship of the common units used to measure distance and area in real estate:

Units of Length

Units of Area