Data on COVID-19 vaccine doses administered in the United States are collected by the following vaccination providers: public health jurisdictions, federal entities, healthcare providers, long-term care facilities, employers, retail pharmacies, and other businesses. These providers report COVID-19 vaccination data to CDC through multiple sources using various reporting methods. Because CDC removes duplicate records, data presented on the COVID Data Tracker might differ from data listed in jurisdictional Immunization Information Systems (IIS) and dashboards. CDC makes every effort to reconcile doses administered that are reported through more than one system.