ABSTRACT Collective memory in humans refers to individual memories that become shared within a community and contribute to social identity, coordination, and cultural continuity. Extensive research shows that collective memory emerges through language‐mediated interaction, social influence, and distributed cognitive mechanisms, supporting cooperation, decision‐making, and cultural transmission. While these processes are well documented in humans, it remains unclear whether, and in what sense, collective memory exists in nonhuman animals. Here we propose a systematic comparative framework for understanding collective memory across species. We first outline the cognitive foundations of collective memory in humans, highlighting the roles of episodic, semantic, autobiographical, and procedural memory, together with mechanisms such as memory conformity, social contagion, memory convergence, transactive memory systems, and ritualized practices. We then examine whether nonhuman animals possess functional precursors of these mechanisms. Across taxa, animals exhibit episodic‐like and semantic‐like memory, social learning, conformity, distributed information systems, and ritualized behaviors that allow groups to store, transmit, and update knowledge beyond individual capacities. These processes support stable traditions, coordinated action, and adaptive responses. Although nonhuman animals show no evidence of autonoetic consciousness or human‐like autobiographical memory, we argue that collective memory should be understood as a graded, non‐dichotomous phenomenon grounded in distributed cognition.