Government Survey: Township, Range, Sections, and Acreage

Township tells you north or south of the baseline. Range tells you east or west of the principal meridian. Then the section number locates the smaller square within that township. Keep those three jobs separate.

Read township and range directions

In T3N, R2W, the township is in the third tier north of the baseline and the second range west of the principal meridian. A tier runs east-west but is numbered north/south. A range runs north-south but is numbered east/west. That difference between the direction a row runs and the direction it is counted causes many mix-ups.

A standard survey township is approximately six miles by six miles, containing 36 sections. A standard section is one square mile, or 640 acres. Actual surveys can contain irregular or fractional sections; use stated actual acreage when supplied. See BLM's explanation of legal land descriptions.

Use the section-number grid

North is at the top; west is on the left. Start at 1 in the northeast corner and follow the alternating rows.

The BLM General Land Office booklet, page 28 illustrates this standard pattern.

What happens at the township boundary?

Draw another grid beyond the edge. Section numbering begins again in the adjacent township; it does not continue to 37.

For example, section 36 is in the southeast corner. In a simplified, aligned township grid, the section immediately south is section 1 of the township to the south. Section 6 is at that next township's northwest corner, several columns away. By contrast, the section immediately north of 36 within the same township is 25.

Use this grid for standard exam-style diagrams. Actual boundary relationships must be checked against the survey; do not use a classroom grid to locate a real property boundary.

Calculate fractional acreage

For acreage, multiply the section's acres by every fraction. For locating the parcel, read the description from the largest tract at the right toward the smaller divisions at the left.

Example: W½ of NE¼ of a standard section.

1. Start with 640 acres.
2. The northeast quarter contains 640 × ¼ = 160 acres.
3. The west half of that quarter contains 160 × ½ = 80 acres.

Do not add ½ and ¼. “Of” means taking part of the preceding tract. A standard township has 36 × 640 = 23,040 acres; use 640 only when the starting tract is one standard section.

Try three practice questions

1. What directions are indicated by T4S, R3E?
2. In the standard grid, which section is directly west of section 14?
3. How many acres are in the S½ of the NW¼ of the SE¼ of a standard section?

Answers and explanations

1. Fourth tier south of the baseline, third range east of the principal meridian.
2. Section 15. In that row the numbers decrease as you move east.
3. 20 acres: 640 × ¼ × ¼ × ½. Work inward from the southeast quarter to locate it.

Keep studying

See the real estate math guide or all exam-prep resources. For help, submit your course, lesson, practice-question number, and diagram or calculation. These are original study exercises.