Identifying oneself as overweight is a risk factor for poor mental health and suicidality independent from objective weight status. The stigma associated with heavier body weight has risen in recent decades and this may have exacerbated the detrimental mental health effects of perceived overweight. In this study, we examined the association between perceived overweight and suicidality in a nationally representative sample (N = 115,180) of US adolescents assessed from 1999 to 2017. We drew on data from the Youth Risk Behavior survey, a biennial population-based survey of students in grades 9-12. Suicidality was gauged by participant reports of past-year suicidal ideation, suicide plans, or suicide attempts. Across all waves, perceived overweight (vs. perceived "normal" weight) predicted a 7.7 percentage point (p < 0.001) increased risk of suicidality after adjustment for age, sex, ethnicity, and BMI. The risk of suicidality associated with perceived overweight increased from 5.7 percentage points in 1999-2001 to 10.1 points in 2015-2017, a difference of 4.4 points (p = 0.001). This growth was most evident after 2009 and was apparent across suicidality measures. Among US adolescents, perceiving one's body as overweight increases risk of suicidality and this risk appears to have grown substantially from 2009 to 2017.