Sierra
Sierra builds AI agents that help leading brands deliver better customer experiences by increasing customer lifetime value and personalizing interactions across multiple channels.
About
Sierra is a conversational AI platform designed for enterprise customer service. It enables companies to deploy branded AI agents that handle real-time queries, automate workflows, and execute actions such as updating CRM records or managing orders. The platform focuses on building AI agents that mirror brand voice, safeguard compliance and privacy, and integrate with enterprise systems for always-on support, aiming to move beyond basic chatbots by leveraging a multi-model architecture, guardrails, and supervision layers to reduce the risk of 'hallucinations' and ensure reliable, high-quality interactions at scale.
Key facts
At-a-glance profile data
- Website
- sierra.ai
- Headquarters
- San Francisco, United States
- Founded
- 2023
- Employees
- 900
- Total funding
- $635M
- Business model
- B2B
Funding rounds
| Date | Round | Amount | Post-money | Lead investors |
|---|---|---|---|---|
| 5 Sept 2025 | Undisclosed round | $350M | - | - |
| 1 Dec 2024 | Funding Round | $175M | $4.5B | - |
| 21 May 2024 | Undisclosed round | $110M | - | Sequoia Capital, Benchmark |
Tech stack
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- Compliance
- SOC 2, HIPAA, ISO 27001, PCI DSS, GDPR, FedRAMP
- Frontend
- Next.js, Tailwind CSS
- Auth
- Okta
- Observability
- incident.io
- Support
- HubSpot
- AI customer support
- Sierra
- CMS / Builders
- Ghost
- CDN
- Cloudflare, Vercel
- Email provider
- Google Workspace
“Anyone at Sierra.ai?. Curious what the culture is like here? Are people selling and make money? Positive customer feedback on the product? Etc etc”
View on Reddit“Can anyone share public docs for Sierra AI or Decagon?. I'm exploring AI platforms Sierra and Decagon and for the life of me can't seem to find a single demo of their platforms or even public docs - am I missing something?”
View on Reddit“Can anyone share Sierra AI or Decagon docs?. I'm exploring AI platforms Sierra and Decagon and for the life of me can't seem to find a single demo of their platforms or even public docs - am I missing something?”
View on Reddit“How much does Sierra AI cost?. Hi all, looking to move from Intercom to something with more firepower. Looking for info on Sierra AI and how much it costs. Intercom is priced per AI resolution and while it's not ideal (bills fluctuate quite…”
View on RedditSome comments are pulled from public discussions around the web (look for the source icon). Quotes are excerpts; click through to read the full thread.
Frequently asked
How much funding has Sierra raised?
Sierra has raised a total of $635M in funding.
How many employees does Sierra have?
Sierra has approximately 900 people on record.