But the number of anti-Muslim groups nearly tripled — from 34 in 2015 to 101 last year.
The SPLC said the tenor of the presidential campaign energized certain sectors of the hate movement.
Donald Trump won the backing of white supremacist David Duke, a former Ku Klux Klan grand wizard. Trump accused Mexican immigrants of being "rapists" and "criminals" and a controversial executive order temporarily barred entry to the U.S. for citizens of seven Muslim-majority nations.
"There is no question that the organizations that aligned themselves with the Trump campaign saw their ranks grow, their prominence grow and their online readership grow," said Heidi Beirich, director of the SPLC's Intelligence Project.
Beirich told NBC News that the number of hate groups has grown over the past two years since dropping to an 11-year low in 2014.
Source: SPLC/NBC News
To maintain its annual count, the SPLC assigns people to watch different hate groups to see whether they develop or fall apart.
The groups are not difficult to identify, because they are actively trying to spread their message, according to Beirich.
Demonstrators shout during a rally against U.S. President-elect Donald Trump in Seattle, Washington, U.S. November 20, 2016. REUTERS/David Ryder
Demonstrators hold signs during a rally against U.S. President-elect Donald Trump in Seattle, Washington, U.S. November 20, 2016. REUTERS/David Ryder
Demonstrators gathered outside of Trump International Hotel and Tower to protest Donald Trump's impending presidency in Chicago on December 1, 2016. (Photo by Max Herman/NurPhoto via Getty Images)
Protestors march against advisers of US President-elect Donald Trump. including Steve Bannon, Trump's chief strategist and senior counselor, at the Kennedy School of Government at Harvard University in Cambridge, Massachusetts on November 30, 2016. / AFP / Ryan McBride (Photo credit should read RYAN MCBRIDE/AFP/Getty Images)
Man wearing a jacket with anti-Trump sticker during a protest against Wells Fargo for partially bankrolling the Dakota Access Pipeline. Los Angeles, California. November 26, 2016. The demonstrators stand in solidarity with the native American Sioux tribe in their efforts to stop the construction of the oil pipeline. President-elect, Donald Trump holds stock in Energy Transfer Partners, the company that is building the pipeline. (Photo by Ronen Tivony/NurPhoto via Getty Images)
A sign seen during a protest against Wells Fargo for partially bankrolling the Dakota Access Pipeline. Los Angeles, California. November 26, 2016. The demonstrators stand in solidarity with the native American Sioux tribe in their efforts to stop the construction of the oil pipeline. President-elect, Donald Trump holds stock in Energy Transfer Partners, the company that is building the pipeline. (Photo by Ronen Tivony/NurPhoto via Getty Images)
TRUMP SOHO HOTEL, NEW YORK, UNITED STATES - 2016/11/21: A legal, nonviolent demonstration was held in front of Trump Soho Hotel (246 Spring St. NY) denouncing Trump's installation of white nationalists, racists and Islamophobes in his administration--foremost Steve Bannon, Jeff Sessions and Michael Flynn. (Photo by Erik McGregor/Pacific Press/LightRocket via Getty Images)
LOS ANGELES, UNITED STATES - NOVEMBER 19: People take part in a rally protest against U.S. President-elect Donald Trump on November 19, 2016 at Downtown Long Beach in Los Angeles, California, United States.
(Photo by Aydin Palabiyikoglu/Anadolu Agency/Getty Images)
PHILADELPHIA, PA - NOVEMBER 19: Larry West, 31, demonstrates against President-elect Donald Trump at Thomas Paine Plaza November 19, 2016 in Philadelphia, Pennsylvania. This is the second protest march today and the 11th consecutive day of anti-Trump protests in Philadelphia, with plans to demonstrate everyday through inauguration day, January 20, 2017. (Photo by Mark Makela/Getty Images)
Hundreds of people gathered in Chicago's Loop for the second weekend of protests against President-elect Donald Trump in Chicago on November 19, 2016. (Photo by Max Herman/NurPhoto via Getty Images)
Diane Knutson (L) and Sandy Hartman of Seattle hold signs as people gather to hold hands in protest of US President-elect Donald Trump on Green Lake in Seattle, Washington on November 19, 2016. / AFP / Jason Redmond (Photo credit should read JASON REDMOND/AFP/Getty Images)
A supporter of U.S. President-elect Donald Trump (R) argues with a man against Trump in Times Square, Manhattan, New York, U.S. on November 9, 2016. REUTERS/Bria Webb
Hispanic demonstrators protest in front of the White House as the polls are counted in the U.S. presidential election in Washington, U.S., November 9, 2016. REUTERS/Joshua Roberts
Supporters of U.S. president-elect Donald Trump and former U.S. presidential nominee Hillary Clinton argue after Trump is declared the winner in Times Square in New York, U.S., November 9, 2016. REUTERS/Mark Kauzlarich
NEW YORK, NY - NOVEMBER 09: An anti-Trump protester yells at a crowd of Donald J. Trump supporters across the street at the Hilton Hotel from where the Republican Presidential nominee is holding his victory celebration at the Hilton Hote on November 9, 2016 in New York City. Donald Trump defeated Democratic presidential nominee Hillary Clinton to become the 45th president of the United States. (Photo by Robert Nickelsberg/Getty Images)
A supporter of U.S. president-elect Donald Trump (front) is shoved by a supporter of former U.S. presidential nominee Hillary Clinton after Trump was declared the winner in Times Square in New York, U.S., November 9, 2016. REUTERS/Mark Kauzlarich
A supporter of U.S. President-elect Donald Trump (L) argues with a man against Trump in Times Square, Manhattan, New York, U.S. November 8, 2016. REUTERS/Bria Webb
TOPSHOT - A Hillary Clinton supporter clashes with a Donald Trump supporter outside the White House early November 9, 2016 in Washington, DC.
Trump stunned America and the world, riding a wave of populist resentment to defeat Hillary Clinton in the race to become the 45th president of the United States. / AFP / Andrew Biraj (Photo credit should read ANDREW BIRAJ/AFP/Getty Images)
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Ibrahim Hooper, national communications director Council on American-Islamic Relations (CAIR) said that Trump's immigration ban — which has been suspended due to a court order — suggested that "what used to be a fringe, extremist ideology of anti-Muslim ideology has now moved from the fringe of society to the center of powers in the White House."
Hooper noted the controversial affiliations of members of Trump's inner circle in the White House.
Former national security adviser Michael Flynn is a board member of ACT for America, which the SPLC categorizes as an "extremist group."
Senior White House strategist Steve Bannon invited SPLC-identified anti-Muslim figures — such as Frank Gaffney and Pamela Geller — on his radio show when he was executive chairman of Breitbart News. And White House counselor Kellyanne Conway worked as a pollster for Gaffney's Center for Security Policy, which the SPLC calls a hate group.
"There's a tremendous level of apprehension and tension in the American Muslim community at a level not seen since 9/11," Hooper added. "People are really wondering where we're going as a nation and what their role and place will be in that nation."
Trump has not directly addressed the spike in hate crimes.
When asked Wednesday about the spike in anti-Semitic incidents across the United States, Trump first cited his electoral victory and the support he had received during the election before addressing the issue.
"I will say that we are going to have peace in this country," the president said. "We are going to stop crime in this country. We are going to do everything within our power to stop long-simmering racism and every other thing that's going on."