Respiratory viruses are a major cause of mortality and morbidity in vulnerable populations. Together, Respiratory syncytial virus (RSV) and Human metapneumovirus (HMPV), are responsible for over ⅓ of serious viral respiratory infections in hematopoietic stem cell transplant (HCT) recipients. Currently, no treatments are available for RSV or HMPV in immunocompromised adults. While monoclonal antibodies (mAbs) show promise as a treatment, challenges arise, including limited efficacy when administered post-infection. Our goal was to enhance the therapeutic efficacy of a newly discovered cross-neutralizing human mAb to RSV and HMPV. We aimed to investigate whether modifying the Fc domain of the antibody could increase its binding to Fcγ receptors (FcγRs) found on different types of immune cells. Activation of FcγRs initiates important cell processes such as clearance of virus-infected cells, also known as Antibody-dependent cellular cytotoxicity (ADCC). This modification potentially makes the antibody a more effective treatment option for RSV and HMPV infections. To do this we looked at the binding kinetics and affinity of modified antibodies to human FcγRIIIa, FcγRIIa and FcγRIIb receptors using Bio-Layer Inferometry (BLI). Our data indicate that certain amino acid modifications or afucosylation of the Fc region can increase the antibody’s binding affinity to different human FcγRs. Since hamsters are an important preclinical model used to determine RSV and HMPV drug efficacy, it was important to examine the binding affinity of our human antibody to hamster FcγR’s. Our data indicate that the wild-type Fc region does bind to the homologous hamster receptors. Moreover, certain modifications in the Fc region led to increased binding to hamster FcγR’s. Together, these data indicate that modifications in the Fc region of human antibodies can increase their binding affinity to both human and hamster FcγRs. This increase in binding affinity could translate to enhanced potency in the preclinical hamster model and in humans.