Ada vs Sierra (2026)

Ada

by Ada

Sierra

by Sierra

Pros

• ✓Ada publishes an 84% automated resolution rate across its platform, with 550+ enterprise AI agents deployed and 6.4 billion customer interactions handled.
• ✓One Reasoning Engine runs agents across voice, chat, email, Messenger, WhatsApp, SMS, Instagram and in-app channels, and Ada Computer lets them act through API, code and MCP tools under the team's controls.
• ✓Ada lists HIPAA, SOC 2, GDPR, PCI DSS and AIUC-1 compliance, keeps zero data retention with LLM providers and states that customer data is never used to train models.

Limitations

• –Pricing is custom with no published rates, and the pricing page leads to an expert review and demo rather than a self-serve plan.
• –G2 reviewers report about 2 months to implement, and Ada's operating model assumes a customer team that manages and coaches its own agents.
• –Ada's published outcomes are its own platform figures and customer case studies rather than an independent benchmark.

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+, most recently at a $15.8B valuation, and said it passed $400M in ARR in October 2026.
• ✓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, AIUC-1, 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 integrations with proprietary systems need custom work through Sierra's integration framework or Agent SDK.
• –Sierra counts 40+ pre-built integrations but does not list them publicly, so buyers confirm coverage in a sales conversation. The MCP route is scoped to ChatGPT Apps, so teams standardizing on another MCP client have no documented endpoint.