"In 2017, being a white nationalist suddenly seemed hip. No longer was it just a movement made up of old men wearing Klan robes or swastika armbands. Now it was young men wearing 'fashy' haircuts, khakis and polo shirts," the SPLC report said.
The largest expansion was among black nationalist groups, up from 193 chapters in 2016 to 233 chapters in 2017.
The SPLC attributes increases in black nationalist hate groups to a "reaction to white racism" and noted that while the black nationalist chapter increase was numerically more than white supremacist groups, their total is still dwarfed by the more than 600 hate groups that practice some form of white supremacist ideology.
"Trump not only energized white supremacists, he provoked a backlash among the Nation of Islam and small, fringe black nationalist groups that see in him a powerful reassertion of the same centuries-old racism that has always fueled their desire to break away from white America," the report states.
The White House did not immediately respond to ABC News’ request for comment on the report.
Specifically, the growth among white supremacist groups was most dramatically seen in groups "most closely aligned with the new president," the report states, giving examples like Patriot Front, the Fraternal Order of Alt Knights and Identity Dixie.
One faction whose growth continues to be steady is anti-Muslim groups. There were 114 anti-Muslim chapters in 2017, the most ever, SPLC said.
As this group increases its presence, "its connections to more hardline racist groups have also grown stronger," SPLC noted.
The SPLC has been criticized by some for the way it labels groups, including by some groups that reject the “hate group” label awarded to them by the SPLC, but it is widely seen to be a leader in the field.
According to the SPLC data, 2017 had the fourth-highest number of hate groups in the country since 1999. The overall number had been decreasing from its peak of 1,018 groups in 2011, dropping to 784 groups in 2014, but has been increasing steadily since.