Polypharmacy, or the use of 5 or more daily medications, is common in adults with multiple sclerosis (MS), and is often due to various physical, cognitive, and emotional symptoms. However, research regarding the association between polypharmacy and cognitive outcomes in MS is sparse. Furthermore, individuals with MS often use medications with anticholinergic properties, which are commonly associated with cognitive impairment and other central nervous system adverse effects. Currently, the utility of scales measuring anticholinergic burden in MS is unknown. This study aims to investigate the relationship between polypharmacy, anticholinergic burden, and objective cognitive performance in MS. We recruited 90 individuals with MS during routine visits at an MS specialty clinic in Kansas City. Participants completed a brief, virtual cognitive assessment and answered questions about their health. Participants provided their medication lists from which we determined polypharmacy and scores on several anticholinergic burden scales. Statistical analyses included Spearman correlations and linear regression models. Approximately 44% of the individuals surveyed met the criteria for polypharmacy. The number of daily medications was negatively correlated with cognitive performance (rs = -0.45, P < .001). Further, the Drug Burden Index accounted for additional variance in cognitive performance beyond that explained by age, education, MS disease duration, and comorbidities [ΔR2 = .12, F(5, 84) = 7.84, P < .001.]. Clinicians should consider the possible negative consequences of polypharmacy when addressing cognitive concerns in MS. Anticholinergic burden scales may be valuable in this regard. Future investigations could explore behavioral and pharmacological interventions aimed at reducing polypharmacy in MS.