In the last two years 17 new groups have been formed, according to a survey carried out by the anti-racism foundation Expo.
The study shows that that there are currently around 30 Nazi groups in Sweden.
Every Swedish county except for Gotland and Jämtland have at least one group, although the highest concentration is found in middle and southern Sweden.
Most of them lack formal leaders and are often inclined to carry out violent actions near their bases of operations.
They call themselves free or independent, but are often tied to networks created by more established organizations such as Info-14 and the Nordic Union (Nordiska förbundet).
Swedish security police service Säpo confirms the increase but are focused on a smaller number of organizations.
“We are primarily interested in the criminal manifestations and thus we’re talking about a handful of groups,” said Säpo analyst Ahn-Za Hagström to Expo’s internet newspaper.
Nazi groups focus mostly on recruiting new members through schools, something which has increased in recent years, according to Säpo.
The four most noteworth Nazi organizations in Sweden are Info-14, Nordic Union, the National Socialist Front (Nationalsocialistisk front), and the Swedish Resistance Movement (Svenska motståndsrörelsen).
Splits and competition between the groups has also been evident in recent years.