The US recorded 518 new coronavirus-linked deaths in the span of 24 hours, according to data published Sunday by Johns Hopkins University.
The record toll, higher than the previous day's increase of 453, brings the country's total number of deaths since the start of the pandemic to 2,409.
The number of cases shot up 21,333 in one day, the data showed.
That is about the same as Saturday's increase of 21,309 but the numbers are counted in real time by Johns Hopkins and should be taken with caution.
With 136,880 total cases, the US has the highest number in the world, ahead of Italy, China and Spain.
New York state, which has become the epicentre of the pandemic in the US, is by far the hardest-hit region, with nearly 60,000 cases and 965 deaths, according to a statement released Sunday by Governor Andrew Cuomo.
Senior US scientist Anthony Fauci, an infectious disease expert and an advisor to President Donald Trump during the crisis, cautiously predicted Sunday that the novel coronavirus could claim between 100,000 and 200,000 lives in the United States.