Sierra, co-founded by Bret Taylor and Clay Bavor and launched in 2024, builds AI agents that handle customer service conversations for large companies. It raised $950 million at a valuation of about $15 billion in May 2026, led by GV and Tiger Global.
At a glance
| Price from | Custom |
| Best for | Large enterprises automating customer service |
From Sierra's own website.
What stands out
- Broad adoption among the largest companies
- Experienced founding team
Worth knowing
- Built for enterprises, not small teams
- Price not published
How it ranks
Sierra is ranked 1st of 10 in Best AI Agent Startups (Lister Score 97.0).
Frequently asked questions
How does Sierra rank on Lister?
Sierra is ranked 1st of 10 in Best AI Agent Startups (Lister Score 97.0).
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