We observed glycan-mediated interactions between the S trimer and glycans at N090, N322, and N546 of ACE2. Thus, variations in glycan occupancy or processing at these sites could alter the affinity of the SARS-CoV-2–ACE2 interaction and modulate infectivity. It is well established that glycosylation states vary depending on tissue and cell type as well as in the case of humans, on age (Krištić et al., 2014), underlying disease (Pavić et al., 2018; Rudman et al., 2019), and ethnicity (Gebrehiwot et al., 2018). Thus, glycosylation portfolios could in part be responsible for tissue tropism and individual susceptibility to infection. The importance of glycosylation for S binding to ACE2 is even more emphatically demonstrated by the direct glycan-glycan interactions observed (Figure 7) between S glycans (at N0074 and N0165) and an ACE2 receptor glycan (at N546), adding an additional layer of complexity for interpreting the impact of glycosylation on individual susceptibility.