Transgender adolescents often categorize themselves in the same way that cisgender adolescents do—that is, as girls/women and boys/men. Potential differences in the extent to which these self‐categorizations matter to transgender and cisgender adolescents, however, have yet to be explored, as has the relative importance transgender adolescents place on their gender compared to their transgender self‐categorization. In the current study, we explored self‐reported identity importance in a sample of 392 primarily White (70%) and multiracial/ethnic (20%) 12–18‐year‐old (M = 15.02) binary transgender (n = 130), binary cisgender (n = 236), and nonbinary (n = 26) adolescents in the United States and Canada. Results revealed that binary transgender adolescents considered their gender self‐categorization to be more important to them than both binary cisgender and nonbinary adolescents did. Most binary transgender adolescents rated their gender self‐categorization as maximally important to them. Additionally, transgender adolescents considered their gender self‐categorization to be more important to them than their transgender self‐categorization (that is, their identification with the label “transgender”). These findings demonstrate that the identities that are often denied to binary transgender adolescents may be the very identities that are most important to them. Results also suggest that gender diverse adolescents with different gender identities may differ in the importance they place on these identities.