This study examines national trends in suicide mortality by method (firearm, poisoning, hanging and asphyxiation, and all other means) among adolescents aged 10-19 years in the US from 1999 to 2020. Using data from the National Center for Health Statistics, the study found that suicide rates increased across all methods during the study period. Firearm suicides increased at an average annual rate of 1.0%, while poisoning, hanging and asphyxiation, and other means of suicide increased at rates of 2.7%, 2.4%, and 2.9%, respectively. Female adolescents showed the most rapid increases in poisoning (4.5%) and hanging and asphyxiation (5.9%) suicides. Black, Asian and Pacific Islander, American Indian and Alaska Native, and Hispanic or Latino adolescents also experienced significant increases in suicide rates, particularly for firearm and hanging and asphyxiation. The study highlights the importance of considering sex, age, and race and ethnicity in understanding suicide trends and developing targeted prevention strategies.This study examines national trends in suicide mortality by method (firearm, poisoning, hanging and asphyxiation, and all other means) among adolescents aged 10-19 years in the US from 1999 to 2020. Using data from the National Center for Health Statistics, the study found that suicide rates increased across all methods during the study period. Firearm suicides increased at an average annual rate of 1.0%, while poisoning, hanging and asphyxiation, and other means of suicide increased at rates of 2.7%, 2.4%, and 2.9%, respectively. Female adolescents showed the most rapid increases in poisoning (4.5%) and hanging and asphyxiation (5.9%) suicides. Black, Asian and Pacific Islander, American Indian and Alaska Native, and Hispanic or Latino adolescents also experienced significant increases in suicide rates, particularly for firearm and hanging and asphyxiation. The study highlights the importance of considering sex, age, and race and ethnicity in understanding suicide trends and developing targeted prevention strategies.