Sierra AI vs Smith.ai Comparison (2025)

Sierra AI delivers a comprehensive conversational platform with multi-channel voice and chat, real-time analytics, and enterprise-grade security out of the box. But you won’t find a price list anywhere—expect to negotiate usage-based fees that climb steeply as you add advanced features or extra channels. Its “build once, run everywhere” Agent OS sounds neat, but customizing flows and integrating with legacy systems often requires dedicated engineering time. The command center offers deep controls, yet teams frequently find it overengineered for routine tasks and in need of training to manage. And despite claims of empathetic, human-like responses, at scale the agents can still stumble over accents or complex queries, leaving gaps that demand human intervention.