Anti-transgender policies and state legislative initiatives that focus on school bathroom use and hormone use have emerged in recent years. These policies are generally written by and voted on by cisgender people, and as such, it is crucial to understand influences on nonaffirming attitudes toward policies that can impact trans youth. The present study aimed to extend research on transphobic attitudes in general to attitudes toward policies that impact youth undergoing transition. Latent variable covariances and structural equation modeling were used to test the relations between transphobia, genderism, homophobia, need for closure, sexual orientation, social dominance orientation, attitudes toward sexual minorities, beliefs about gender roles, aggression, religious fundamentalism, and contact with sexual and gender minority individuals, as they are related to attitudes toward hormone use and bathroom use for trans youth. Analyses of data from a sample of 248 cisgender adults indicated that genderism and transphobia was associated with attitudes toward gender-affirming hormone use and bathroom use for trans youth; need for closure was associated with gender-affirming attitudes toward bathroom use, but was not associated with hormone use. Sexual orientation was linked to attitudes toward gender-affirming policies, such that nonheterosexual participants had more affirming attitudes toward trans youths' bathroom use, but not hormone use. Implications for future research, advocacy efforts to promote rights for trans youth, and clinical work with trans youth and/or parents/guardians of trans youth are discussed. (PsycInfo Database Record (c) 2022 APA, all rights reserved).