Finding UTM References

Anyone can read Universal Transverse Mercator (UTM) grid references quickly and accurately.

Diagram - UTM grid
Diagram - UTM grid

To find the UTM co-ordinate of the church (symbolized as Church symbol) on the example of a 1/50 000 scale map grid above, proceed as follows:
  1. First, find the number of the grid line to the West of Church symbol. This is observed to be 91.
  2. Now, estimate the number of tenths Church symbol is to the East of this grid line. This is observed to be about 6, and when combined with the figure determined in Step 1, gives the EASTING as 916.
  3. Next, find the the number of the grid line South of Church symbol This is observed to be 94.
  4. Now, estimate the number of tenths Church symbol is North of this grid line. This is observed to be about 4, and when combined with the figure determined in Step 3, gives the NORTHING as 944.
  5. By combining the Easting and Northing, the map reference obtained for Church symbol is therefore 916944.

Note: Such map references repeat every 100 kilometres. You should quote the map number if there is a chance of ambiguity.

UTM References on 1/250 000 Scale Maps

Diagram - 1:250 000 UTM grid
Diagram - 1:250 000 UTM grid (Note, example is not drawn to scale)

When using a UTM co-ordinate from a 1/250 000 scale NTS map, be sure to give the letter of the large square concerned. For example, the reference of the church on the map to the right is NT 9393

Using a Roamer

A roamer is a device for reading UTM co-ordinates on topographic maps. Use a roamer as illustrated below

Diagram - Using a roamer on a UTM grid.
Diagram - Using a roamer on a UTM grid. (Note, example is not drawn to scale)

Always measure over to the East and then up to the North. In other words, find the Easting, then the Northing.

Further Reading: Find out more about the National topographic System, how to navigate with a topographic map, Map Scale, and UTM Projection used on NTS maps.