Racial-ethnic disparities in COVID-19 vaccination are well documented. The extent to which racism, manifested at the individual and ZIP code levels, explains disparities in early vaccination uptake remains unclear. Data from a statewide poll of California registered voters (N=10,256), conducted between April 29 and May 5, 2021, linked to area-level resource data, were analyzed. Weighted multivariable logistic regression models examined racial disparities in COVID-19 vaccination. Decomposition analyses quantified how much of the observed racial disparities in vaccination were explained by racial discrimination and social disadvantage (i.e., educational attainment, 2019 household income, and ZIP code social vulnerability). Latinx (64.6%) and Black (66.7%) adults were less likely to have at least 1 COVID-19 vaccine dose by April or May 2021 than White adults (74.7%). In adjusted analyses, Latinx (AOR=0.69, 95% CI=0.57, 0.84) and Black (AOR=0.51, 95% CI=0.37, 0.70) adults had a lower likelihood of being vaccinated than Whites. Social disadvantage accounted for 77.4% (p<0.05) and 35.8% (p<0.05) of the explainable variation in Latinx-White and Black-White disparities, respectively. Self-reported racial discrimination was not associated with COVID-19 vaccination in adjusted analyses. Social disadvantage but not self-reported racial discrimination explained racial-ethnic disparities in COVID-19 vaccination in California. Removing resource-related barriers may help to increase the relatively low COVID-19 vaccination rates among Black and Latinx populations.