Westerholm is a Swedish-language surname, more common in Finland than in Sweden.[1]
As of 2014, 53.5% of all known bearers of the surname Westerholm were residents of Finland (frequency 1:4,284), 25.0% of Sweden (1:16,439), 15.6% of the United States (1:963,337) and 1.0% of Estonia (1:57,464).
In Finland, the frequency of the surname was higher than national average (1:4,284) in the following regions:
In Sweden, the frequency of the surname was higher than national average (1:16,439) in the following counties:[2]