The five men and a woman were suspected of instigating and carrying out terrorism, and being members of National Action, a statement from West Midlands Police said.
The arrests were carried out in an intelligence-led operation, police said.
The men aged 21-28 were held in Cambridge, Banbury, Wolverhampton, Leicester and Stockport. A 37-year-old woman was arrested in Banbury, Oxfordshire.
National Action was proscribed as a terror organization in December 2016.
British counter-terror officers, last year, arrested a number of individuals amid investigations into the banned neo-Nazi group, including serving British soldiers, three of whom were charged with terror offenses.
The anti-Semitic and white supremacist group had celebrated the murder of Labor MP Jo Cox in June 2016 by far-right extremist Thomas Mair.
The group describes itself as a “National Socialist youth organization.” However, Home Secretary Amber Rudd described it as “racist, anti-Semitic and homophobic.”
“It has absolutely no place in a Britain that works for everyone,” she added.
All six are being held at a police station in the West Midlands and a number of properties are being searched, police said.