1.3 Legal Descriptions and Surveys

Key Takeaways

  • The three accepted legal descriptions are Metes and Bounds, Rectangular (Government) Survey, and Lot and Block (recorded plat).
  • A metes-and-bounds description must start and return to the same point of beginning (POB) to form a closed loop.
  • In the rectangular survey system a section is 1 mile square and contains 640 acres; a township is 6 miles square (36 sections).
  • One acre = 43,560 square feet; this conversion underlies most area calculations.
  • A street address is never an acceptable legal description; benchmarks/datum and a surveyor establish vertical (air/subsurface) measurements.
Last updated: June 2026

Three Methods of Legal Description

A legal description identifies a parcel precisely enough that a court could locate it; a street address or tax-parcel number alone is not a legal description. Three methods are accepted nationally.

MethodHow it worksWhere used
Metes and boundsMeasures distances (metes) and directions/boundaries (bounds) from a Point of Beginning (POB), tracing the perimeter back to the POBOriginal 13 states, irregular parcels
Rectangular (Government) SurveyGrid of principal meridians and base lines forming townships and sectionsMost states west of the Appalachians
Lot and block (recorded plat)References a lot/block on a subdivision plat map recorded in public recordsSubdivisions everywhere

Metes and bounds rule: the description must always close — it must return to the exact Point of Beginning. If it does not return to the POB, the description is defective.

The Rectangular (Government) Survey System

This system divides land using principal meridians (north-south lines) and base lines (east-west lines). The grid creates the following units — these numbers are heavily tested:

UnitSizeContains
Township6 miles x 6 miles = 36 sq miles36 sections
Section1 mile x 1 mile = 1 sq mile640 acres
Quarter section1/2 mile x 1/2 mile160 acres
Quarter-quarter section1/4 mile x 1/4 mile40 acres

Key constants to memorize:

  • 1 section = 640 acres
  • 1 township = 36 sections
  • 1 acre = 43,560 square feet
  • 1 mile = 5,280 feet

Sections within a township are numbered 1 to 36 in a boustrophedonic (serpentine) pattern: Section 1 is the northeast corner, numbering snakes west to Section 6, drops down, and reverses east — ending at Section 36 in the southeast corner.

Test Your Knowledge

How many acres are in a parcel described as 'the SW 1/4 of the NE 1/4 of Section 8'?

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D

Worked Acreage Calculation

Problem: A parcel is described as the 'N 1/2 of the SW 1/4 of the NW 1/4' of a section. How many acres, and at $3,000/acre, what is the land value?

Step 1 — multiply the fractions by 640:

640 x (1/2) x (1/4) x (1/4) = 640 / 32 = 20 acres

Step 2 — value:

20 acres x $3,000 = $60,000

Shortcut: multiply all the denominators together (2 x 4 x 4 = 32), then divide 640 by that product. The numerator on the first fraction (N 1/2) keeps it from being 10 acres — always apply each numerator.

Converting to square feet

If a question gives you a rectangular lot of 0.5 acre and asks for square footage:

0.5 x 43,560 = 21,780 sq ft

And reversing: a 87,120 sq ft parcel is 87,120 / 43,560 = 2 acres. The 43,560 conversion is the most important survey number on the test.

Surveys, Datum, and Vertical Measurement

A survey is performed by a licensed surveyor and produces a legal description plus a survey map showing boundaries, improvements, and encroachments.

Vertical measurements (needed for condominiums, air rights, and subsurface rights) rely on a datum — an established reference point of elevation (the U.S. Geological Survey uses mean sea level). A benchmark is a permanent marked reference point whose elevation is known relative to the datum.

  • Air rights — ownership of space above the surface, important for high-rise condos and air-lot descriptions.
  • Subsurface rights — ownership below the surface (minerals, water, oil).

Trap: a condominium unit cannot be described by lot and block alone, because it floats above the ground. Its legal description must use datum/benchmark elevations to define the unit's vertical boundaries (floor and ceiling elevations) plus a reference to the recorded condominium plat.

Lot and block in practice

The lot and block method (also called the recorded plat or subdivision system) is the most common description for residential subdivisions. A developer surveys raw acreage, divides it into numbered lots within blocks, and records a plat map in the county recorder's office. Each lot is then described simply: 'Lot 7, Block 3, Maple Ridge Subdivision, as recorded in Plat Book 14, Page 22.'

The recorded plat itself usually started life as a metes-and-bounds or rectangular-survey description of the whole tract, so the methods nest inside each other. The exam likes to test that a single parcel can be described by more than one valid method.

A combined acreage-and-price drill

Problem. A developer buys the E 1/2 of the NW 1/4 of a section for $4,500 per acre, then sells half of it as 10 equal subdivision lots. How many acres did he buy, and what is the per-lot land cost?

  • Acres bought: 640 x (1/2) x (1/4) = 80 acres
  • Total cost: 80 x $4,500 = $360,000
  • Half developed: 80 / 2 = 40 acres into 10 lots = 4 acres each
  • Land cost per lot: $360,000 x (40/80) / 10 = $180,000 / 10 = $18,000 per lot

The step that trips candidates is applying the numerator of the E 1/2 and the NW 1/4 before multiplying by 640. Always read the fractions from the smallest unit outward.

Test Your Knowledge

Which of the following is NOT an acceptable legal description for conveying title?

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D