The relationship of the Milbanke Sound Cones and to other volcanoes throughout British Columbia is not clear. In some classifications, they are grouped with the Anahim Volcanic Belt because they are parallel with its east-west trend. However, this grouping is not widely accepted because the volcanoes are much younger than other magmatic features at the western end of the Anahim Volcanic Belt. The cause of this significant age change is because the Anahim Volcanic Belt has its origins from the North American Plate moving over the hypothesized Anahim hotspot. This is a mantle plume that is likely responsible for volcanism throughout the Anahim Volcanic Belt. Individual Anahim volcanoes generally become older west of Nazko Cone, indicating that the North American Plate is moving in a westerly direction with respect to the hotspot, carrying the volcanoes along with it at a rate of to per year. Thus the hotspot model can not be used to explain the formation of the Milbanke Sound Group. However, the volcanic group is near the remnants of a 14 to 12 million year old magmatic feature that is interpreted to define the westernmost end of the Anahim hotspot track.