To shed light on recent trends in payer coverage of biosimilars, this paper analyzes commercial medical benefit coverage and price trends for biosimilars and reference biologics over the period 2018–2021 in three disease areas: breast cancer and non-small cell lung cancer (NSCLC), colorectal cancer and chronic lymphocytic leukemia (CLL), and neutropenia (a side effect of chemotherapy). This analysis shows that medical benefit coverage for biosimilars in these disease areas increased and prices declined during the period studied. Additionally, the share of preferentially covered biosimilars more than tripled.