Early in the COVID-19 pandemic, disruptions to sexual health services and changes to sexual behavior due to the first COVID-19 lockdowns were common among U.S. gay, bisexual, and other men who have sex with men (GBMSM). Less is known about the persistence of these changes after this initial lockdown period. These changes have long-term implications for HIV prevention for current and future pandemic periods. This study collected information on COVID-related impacts on sexual behavior and HIV-related health service disruptions from a cohort of U.S. GBMSM at three time points during the COVID-19 pandemic. We observed that COVID-related disruptions to sexual behavior continued from early lockdown periods through December 2020. Although early interruptions to pre-exposure prophylaxis (PrEP) access resolved in later 2020 and interruptions to antiretroviral therapy (ART) adherence were minimal, extended disruptions were observed in HIV testing, sexually transmitted infection (STI) testing, HIV care clinical visits, and HIV viral load testing. Although sexual behavior did not return to prepandemic levels in late 2020, the reduced access to HIV prevention, testing, and treatment services during this period could result in an overall increased HIV transmission rate, with long-term impacts to the trajectory of the U.S. HIV epidemic. Additional resources and programs are needed to address challenges created by the COVID-19 pandemic, as well as prepare for future potential pandemics and other disruptive events.