Cresta vs Sierra (2026)

Cresta

by Cresta Intelligence Inc.

Sierra

by Sierra

Pros

• ✓Autonomous AI Agents across voice, chat, and SMS in 30+ languages with shared memory: context is never lost across channels, handoffs, or between human and AI agents, with real-time action-taking via CRM, billing, and scheduling integrations through Model Context Protocol and API-based function calling.
• ✓Deepest telephony integration coverage in the category: native connections to Five9, Amazon Connect, Nice, Genesys, Avaya, LivePerson, Twilio, and Cisco mean Cresta deploys into virtually any existing contact center infrastructure without rip-and-replace.
• ✓One of the most comprehensive compliance stacks in the AI customer support category: SOC 2 Type II, ISO/IEC 27001, ISO/IEC 42001:2023, ISO/IEC 27701, HIPAA, GDPR, CCPA, CPRA, SOC 3 and TISAX, plus certified Level 1 service provider status under PCI DSS, with Cresta among the first companies certified under ISO 42001 for AI governance.

Limitations

• ⚠Custom pricing with no published tiers, no pricing page and no self-serve trial: enterprise buyers must engage sales to get a quote, which lengthens evaluation compared with vendors that publish rates openly.
• ⚠Enterprise implementation timeline of 2 to 8 weeks: deploying across telephony, CRM, and knowledge integrations requires coordination with Cresta's onboarding team, making it unsuitable for teams that need AI agents live in days rather than weeks.
• ⚠No published autonomous resolution rate benchmark from Cresta directly: Snap Finance documented containment improvement from 6% to 33% as a third-party case study, but Cresta publishes no standard resolution rate metric of its own.

Pros

• ✓Co-founded by Bret Taylor, a former Salesforce co-CEO and OpenAI board chair, and Clay Bavor, an 18-year Google veteran who led Google Labs and Lens. Sierra has raised $1B+ at a $15.8B valuation and reports $150M+ ARR.
• ✓Outcome-based pricing charges per resolved interaction rather than per seat or conversation, so what a buyer pays tracks resolutions delivered rather than seats purchased.
• ✓Compliance covers FedRAMP High, SOC 2 Type II, ISO 27001, ISO 42001, HIPAA, GDPR and CCPA, with named audit reports for SOC 2 and HIPAA available under NDA through the trust center.

Limitations

• ⚠Sierra publishes no pricing page, no rate card, no minimum commitment and no per-outcome rate. Every commercial term including the definition of a resolved outcome is negotiated directly.
• ⚠Deployment is sales-led with no self-serve signup. Published customer go-live timelines run from two to ten weeks, and integration changes route through Sierra's engineering team rather than self-service configuration.
• ⚠There is no connector marketplace and no pre-built integration library, verified against six candidate paths. The MCP route is scoped to ChatGPT Apps, so teams standardizing on another MCP client have no documented endpoint.