Coldoch broch stands on a small but distinct knoll, overlooking the flood plain of the Goodie Water and River Forth below. The land falls away steeply to the south, but the broch is on a similar level to the farmland to its north, and the entrance is on the east side.
The broch has an interior diameter of between 8.4m and 9.0m, but the site is quite overgrown so it is difficult to make out a lot of features. The walls can be traced all around the outside of the broch, and stand to a maximum height of around 2.4 metres.
The thickness of the walls varies from 5.2m to 5.8m, and they have various small stone-built niches on their inner face. Within the walls are three chambers, and the fallen lintel above an entrance to one of them can be seen.
Also within the thickness of the wall is an intra-mural staircase. The entrance to it is clearly visible, although any traces of the steps themselves are now covered by vegetation.