Thus, as compared with neutralization of USA-WA1/2020, neutralization of Δ242-244+D614G virus was similar and neutralization of the B.1.351-spike virus was weaker by approximately two thirds. Our data are also consistent with poorer neutralization of the virus with the full set of B.1.351-spike mutations than virus with either subset of mutations and suggested that virus with mutant residues in the receptor-binding site (K417N, E484K, and N501Y) is more poorly neutralized than virus with Δ242-244, which is located in the N-terminal domain of the spike protein.