Workplace and non-workplace homicides in the United States (U.S.) have declined for over 30 years until recently. This study was conducted to address the change in trends for both workplace and non-workplace homicides and to evaluate the homogeneity of the change in workplace homicides by specified categories. Joinpoint and autoregressive models were used to assess trends of U.S. workplace and non-workplace homicides utilizing surveillance data collected by the Bureau of Labor Statistics and the Federal Bureau of Investigation from 1994 through 2021. Both workplace and non-workplace homicides decreased significantly from 1994 through 2014. Workplace homicides showed no significant trend from 2014 through 2021 (p = 0.79), while non-workplace homicides showed a significant average annual increase of 4.1% from 2014 through 2020 (p = 0.0013). The large decreases in the trend of workplace homicides occurring during a criminal act, such as robbery, leveled off and started to increase by the end of the study period (p < 0.0001). Declines in workplace homicides due to shootings also leveled off and started to increase by the end of the study period (p < 0.0001). U.S. workplace and non-workplace homicide rates declined from the 1990s until around 2014. Trends in workplace homicides varied by the types of the homicide committed and by the type of employee that was the victim. Criminal-intent-related events, such as robbery, appear to be the largest contributor to changes in workplace homicides. Researchers and industry leaders could develop and evaluate interventions that further address criminal-intent-related workplace homicides.