Attorneys for James Fields, 22, of Maumee, Ohio, had urged the judge to consider a lesser sentence for the Aug. 12, 2017, attack that also injured 19 people at the Unite the Right rally.
The rally proved a critical moment in the rise of the "alt-right," a loose alignment of fringe groups centered on white nationalism and emboldened by President Donald Trump's 2016 election.
Trump was criticized from the left and right for initially saying there were "fine people on both sides" of the dispute between neo-Nazis and their opponents at the rally. Subsequent alt-right gatherings failed to draw crowds the size of the Charlottesville rally.
Earlier, authorities played a graphic videotape of Fields using his car as a weapon to attack the crowd of counterprotesters, including Heather Heyer. The violence shook the college town at the end of two days of rallies by avowed white nationalists, who marched first with torches and later with medieval-style shields.
Heyer's parents described the grief of losing their daughter.
"It was an incident I will never fully recover from," said Heyer's father, Mark Heyer.
Her mother, Susan Bro, described herself as "deeply wounded" and recounted crying uncontrollably at times.
Ahead of Friday's sentencing hearing, prosecutors noted that Fields had long espoused violent beliefs. Less than a month before the attack he posted an image on Instagram showing a car plowing through a crowd of people captioned: "you have the right to protest but I'm late for work."
Even after the attack, Fields remained unrepentant, prosecutors said, noting that in a Dec. 7, 2017, phone call from jail with his mother, he blasted Bro for her activism after the attack.
"She is a communist. An anti-white liberal," Fields said, according to court papers filed by prosecutors. He rejected his mother's plea to consider that the woman had "lost her daughter," replying, "She's the enemy."
Fields pleaded guilty to the federal hate crime charges in March under a deal with prosecutors, who agreed not to seek the death penalty.
He was photographed hours before the attack carrying a shield with the emblem of a far-right hate group. He has identified himself as a neo-Nazi.Fields' attorneys suggested he felt intimidated and acted to protect himself. They asked for mercy, citing his relative youth and history of mental health diagnoses.