Bearing in surveying is the angle that describes the direction of a line on the ground with respect to a reference north or south line, used to locate and plot points accurately in a survey.

What is bearing in surveying?

In land surveying, a bearing is the horizontal (plan) angle between a reference meridian (usually north or south) and a survey line.

It is measured clockwise or anticlockwise from either north or south toward east or west and is always taken as an acute angle less than 90 degrees in the common “bearing” notation.

A typical bearing is written like: N 60° E, S 25° W, etc., where the first letter is the starting meridian (N or S), the angle is the magnitude, and the last letter is the direction towards which the line turns (E or W).

Bearings are fundamental in surveying to fix the orientation of lines, define boundaries, and transfer directions from the field to maps or drawings.

Example: A line from point A to point B with bearing N 30° E means: start facing north at A, rotate 30° towards the east, and that direction points to B.

Reference meridians used

Survey bearings are always measured with respect to some meridian (reference north–south line).

Common reference meridians include:

  • True meridian (geographic north based on Earth’s axis).
  • Magnetic meridian (direction shown by a magnetic compass needle).
  • Grid meridian (north of a map projection grid, e.g., UTM grid north).
  • Arbitrary or assumed meridian (a convenient chosen line in a local survey).

Depending on which meridian you use, you get: true bearing, magnetic bearing, grid bearing, or arbitrary bearing.

Systems of bearing expression

Surveyors commonly use two main systems for expressing bearings.

[4][3][7] [4][5][1] [4][1]
System How angle is measured Typical notation
Quadrantal (Reduced Bearing) Acute angle (0°–90°) measured from N or S toward E or W. N 40° E, S 20° W, etc.
Whole Circle Bearing (WCB) Angle (0°–360°) measured clockwise from north. 40°, 135°, 250°, 310°, etc.
  • Quadrantal bearings clearly show the quadrant (NE, SE, SW, NW) using N/S and E/W letters.
  • Whole circle bearings are convenient for computation and traverse adjustment because they are a single 0°–360° angle from north.

Why bearings matter in surveying (practically)

Bearings are used to:

  1. Define the direction of boundary lines in land records and title deeds.
  1. Establish the relative positions of points in traverses and control networks.
  1. Transfer direction from field instruments (compass, theodolite, total station, GNSS) onto maps and CAD drawings.
  1. Check survey closures and compute coordinates by converting bearings and distances into northings and eastings.

A simple way to picture it: a bearing is like giving your friend both a heading and a turn angle so they can walk from one peg to the next without seeing the whole map.

TL;DR:
In surveying, a bearing is the horizontal angle that gives the direction of a line from north or south toward east or west, referenced to a chosen meridian (true, magnetic, grid, or arbitrary), and written in forms like N 35° E or as whole-circle angles from north.

Information gathered from public forums or data available on the internet and portrayed here.