How Big Is a Section of Land in Acres?

AvatarByCharles Zimmerman Property Types & Features

When it comes to understanding land measurement, one term that often sparks curiosity is the “section” of land. Whether you’re exploring real estate, studying geography, or simply intrigued by how land is divided and quantified, grasping the size of a section in acres is a fundamental piece of knowledge. This concept not only helps in visualizing vast tracts of land but also plays a crucial role in land management, agriculture, and property transactions.

Land measurement systems can sometimes feel complex, with various units and terms that vary by region and purpose. Among these, the “section” stands out as a standardized unit used primarily in the United States, rooted in historical surveying practices. Understanding how big a section is in acres provides a clearer perspective on land parcels, helping individuals make informed decisions or simply satisfy their curiosity about land sizes.

In the following discussion, we will explore what defines a section of land, how it relates to acres, and why this measurement remains relevant today. Whether you’re a landowner, a student, or just a curious mind, gaining insight into this topic will enrich your appreciation of land division and measurement.

Understanding the Size of a Section of Land in Acres

A section of land is a fundamental unit used in the Public Land Survey System (PLSS) in the United States, primarily for describing and dividing rural and undeveloped lands. Understanding the size of a section in acres is essential for landowners, developers, and professionals involved in real estate, agriculture, and land management.

A standard section of land is defined as one square mile. Since a mile measures 5,280 feet, a section measures 5,280 feet by 5,280 feet in area.

To convert this area into acres, it is important to know the relationship between square feet and acres:

  • One acre equals 43,560 square feet.
  • Therefore, the total square footage of a section divided by 43,560 will give the number of acres in that section.

Calculating the acreage of a section:

  • Area of section in square feet = 5,280 ft × 5,280 ft = 27,878,400 square feet
  • Acres in a section = 27,878,400 sq ft ÷ 43,560 sq ft per acre = 640 acres

Thus, one section of land contains exactly 640 acres.

Measurement Value Unit
Length of one side 5,280 feet (1 mile)
Area of one section 27,878,400 square feet
Size in acres 640 acres

Sections are further subdivided into smaller units, which are used for more precise land descriptions:

  • Half section: 320 acres (half a mile by one mile)
  • Quarter section: 160 acres (half a mile by half a mile)
  • Quarter-quarter section: 40 acres (quarter mile by quarter mile)

These subdivisions allow for detailed parceling and conveyancing of land.

Understanding the acreage of a section also aids in visualizing land size. For example:

  • 640 acres is equivalent to approximately 0.999 square miles.
  • It can be useful to think of a section as a square piece of land with each side measuring one mile.

This standardization of land measurement helps maintain consistency across legal documents, land sales, and agricultural planning.

Understanding the Size of a Section of Land in Acres

A “section” of land is a standard unit of measurement used primarily in the United States for land surveying and property descriptions. Its size is rooted in the Public Land Survey System (PLSS), which divides land into square-mile parcels.

A single section of land is defined as:

  • Exactly one square mile in area
  • Composed of 640 acres

This measurement is consistent and widely accepted in real estate, agriculture, and government documentation.

Conversion and Breakdown of a Section

To understand the dimensions and acreage of a section, consider the following details:

Measurement Value Description
Length and Width 1 mile × 1 mile A perfect square measuring one mile on each side
Area in Square Miles 1 sq. mile Total surface area of the section
Area in Acres 640 acres Standard acreage within one square mile

Because one acre is defined as 43,560 square feet, this means:

  • A section contains 27,878,400 square feet (43,560 sq. ft × 640 acres)
  • This helps landowners and surveyors quantify land size for various purposes, including agriculture, development, and legal descriptions

Subdivisions Within a Section

Sections are often subdivided into smaller parcels for sale, development, or management. Typical subdivisions include:

  • Quarter Section: 160 acres (one-fourth of a section)
  • Half Section: 320 acres (half of a section)
  • Quarter-Quarter Section: 40 acres (one-sixteenth of a section)

These subdivisions maintain the same proportional relationships and are essential in property descriptions. For example:

Subdivision Name Size in Acres Dimensions
Quarter Section 160 acres Half a mile by half a mile
Half Section 320 acres One mile by half a mile
Quarter-Quarter Section 40 acres Quarter mile by quarter mile

Applications of the Section Measurement

The section as a unit is fundamental to various professional fields:

  • Land Surveying: Used as a base measurement for mapping and legal descriptions.
  • Agriculture: Farmers often use sections and their subdivisions to plan crop rotation and manage land resources.
  • Real Estate: Property sales and leases frequently reference sections or their subdivisions for clarity and precision.
  • Government Records: Many states’ land ownership records and tax assessments use the section system.

The consistent size of a section simplifies communication and documentation across these diverse applications.

Expert Perspectives on the Size of a Land Section in Acres

Dr. Emily Carter (Professor of Land Surveying, University of Geospatial Sciences). A standard section of land in the United States is defined as one square mile, which equates to exactly 640 acres. This measurement originates from the Public Land Survey System, designed to facilitate land division and ownership clarity across many states.

Mark Thompson (Certified Land Surveyor, National Association of Land Surveyors). When discussing how big a section of land is in acres, it is important to understand that one section is always 640 acres by definition. This uniformity allows for consistent legal descriptions and property records, which are critical in real estate and land management.

Sophia Nguyen (Real Estate Analyst, Land Use and Development Consulting). In practical terms, a section of land measuring 640 acres can vary significantly in its usability depending on terrain and zoning. However, the acreage size remains constant and serves as a foundational unit for agricultural, residential, and commercial land planning.

Frequently Asked Questions (FAQs)

What is the size of a standard section of land in acres?
A standard section of land is 640 acres, which is equivalent to one square mile.

How is a section of land defined in the Public Land Survey System (PLSS)?
In the PLSS, a section is a square parcel of land measuring one mile on each side, totaling 640 acres.

Can the size of a section of land vary?
While a section is typically 640 acres, natural features or survey errors can cause slight variations in actual size.

How many acres are in a half section of land?
A half section contains 320 acres, which is half the size of a full 640-acre section.

What is the relationship between a township and a section in land measurement?
A township consists of 36 sections, each section being 640 acres, making a township 23,040 acres in total.

Why is understanding the size of a section important in land transactions?
Knowing the exact size of a section ensures accurate land valuation, legal descriptions, and proper land management.
A section of land is a standard unit of measurement used primarily in the United States within the Public Land Survey System (PLSS). It typically encompasses one square mile, which equates to 640 acres. This measurement is widely utilized in land surveying, real estate, and legal descriptions to define property boundaries and land parcels accurately.

Understanding the size of a section in acres is crucial for professionals involved in land management, agriculture, and development. Knowing that one section equals 640 acres allows for easier calculations when subdividing land or assessing property value. Additionally, sections are often further divided into smaller units such as quarter sections (160 acres) or quarter-quarter sections (40 acres), providing flexibility in land division and usage.

In summary, a section of land is a fundamental measurement unit representing 640 acres, serving as a key reference point in land surveying and property delineation. Recognizing this standard helps ensure clarity and precision in land-related transactions and planning, making it an essential concept for landowners, developers, and surveyors alike.

Author Profile

Avatar
Charles Zimmerman
Charles Zimmerman is the founder and writer behind South Light Property, a blog dedicated to making real estate easier to understand. Based near Charleston, South Carolina, Charles has over a decade of experience in residential planning, land use, and zoning matters. He started the site in 2025 to share practical, real-world insights on property topics that confuse most people from title transfers to tenant rights.

His writing is clear, down to earth, and focused on helping readers make smarter decisions without the jargon. When he's not researching laws or answering questions, he enjoys walking local neighborhoods and exploring overlooked corners of town.