Following the signing of peace agreements, post-accord societies often remain deeply divided across group lines. There is a need to identify antecedents of youth's support for peace and establish more constructive intergroup relations. This article explored the effect of out-group trust, intergroup forgiveness, and social identity on support for the peace process among youth from the historic majority and minority communities in Belfast, Northern Ireland. The sample comprised 667 adolescents (49% male; M = 15.74, SD = 1.99 years old) across two time points. The results from the structural equation model suggested that out-group trust was related to intergroup forgiveness over time, while forgiveness related to later support for the peace process. Strength of in-group social identity differentially moderated how out-group trust and intergroup forgiveness related to later support for peace among youth from the conflict-related groups (i.e., Protestants and Catholics). Implications for consolidating peace in Northern Ireland are discussed, which may be relevant to other settings affected by intergroup conflict.