The yearly increase is the highest recorded since the National Highway Traffic Safety Administration's (NHTSA) current traffic fatality tracking system was implemented in 1975.
"We face a crisis on America's highways that we must address collectively," said USDOT Secretary Pete Buttigieg.
The USDOT released a strategy in January to reduce the alarmingly high number of traffic deaths on American roads.
Traffic deaths increased after coronavirus lockdowns were lifted in 2020, as more drivers engaged in risky behavior such as speeding and driving while impaired by drugs or alcohol.
Traffic deaths in 2020 will be 6.8 percent higher than in pre-pandemic 2019.
Traffic fatalities are expected to rise in 44 U.S. states and the District of Columbia.
NHTSA said the fatality rate in 2021 fell slightly to 1.33 fatalities per 100 million miles traveled down from 1.34 million in 2020, which was the highest rate since 2007.
One factor for the big jump in 2020 was that drivers who remained on the roads engaged in riskier behavior, NHTSA said.
As U.S. roads became less crowded, some motorists perceived police were less likely to issue tickets because of COVID-19, experts say.