Source-backed analysis8
Review basis
Research-based review: the AppDuo Editorial Team compiled it from official pages, documentation, app stores, press and user feedback, without hands-on testing. Every claim links to a source with the date it was checked.
8 reference sourcesInformation updated Nov 10, 2026
How we review
Sierra Review
Customer-experience AI agents for large enterprises, priced by outcome
By AppDuo Editorial Team · Updated
- Web
- API
On this page
Decide at a glance
Our verdict
Sierra suits large enterprises deploying AI agents across chat, voice and email at scale, paying per outcome rather than per seat or token. The trade-offs are unpublished pricing, a contract-defined notion of success, and very few public user reviews to check vendor claims against.
Best for: Large enterprises with high customer-conversation volume that need one agent across chat, SMS, WhatsApp, email and voice
Skip it if: Small businesses that need public pricing and self-serve signup
Pros
- Outcome-based fees; unresolved or escalated conversations are generally not charged
- One agent deployed across chat, SMS, WhatsApp, email, voice and ChatGPT
- Many published security and compliance attestations, plus monitoring tools (Insights, Compliance Console)
Cons
- No published pricing; cost and the definition of a successful outcome are set by contract
- Very few public user reviews, so vendor performance figures are hard to verify
All pros and cons · Who is it for?
Pros
- Steady releases: Ghostwriter, Agent Studio, Horizon, Voice Personas
Cons
- Enterprise-only, and buying goes through Sierra's sales team
Best for
- Regulated sectors such as finance and healthcare that want a vendor publishing many compliance attestations
Skip it if
- Teams that want to try before buying: Sierra advertises no free trial
Problems it solves
Experience & key features
Sierra is an enterprise conversational AI platform from Sierra Technologies. Per CMSWire, it was co-founded by Bret Taylor (former Salesforce co-CEO) and Clay Bavor (former Google Labs lead) and launched in February 2024. The homepage pitches it for revenue growth and customer lifetime value, not only customer service.
Ghostwriter builds agents from SOPs, call transcripts or plain-language goals. Agent Studio lets teams build with or without engineers, and Insights adds Explorer, Monitors, Experiments and Observability. One agent can answer across chat, SMS, WhatsApp, email, voice and ChatGPT. Horizon (launched 16 July 2026) targets tasks that run for days or weeks, such as originating a loan.
Pricing is the main differentiator: Sierra lists no prices and charges per outcome, such as a resolved conversation or a retained customer, and handoffs to humans are generally free. SalesforceBen points out that defining success, and who decides it, is hard, so buyers should pin this down in the contract.
On scale, CMSWire reported in May 2026 a $950M raise led by Tiger Global and GV at a valuation above $15B, with more than 40% of the Fortune 50 as customers; Sierra's blog of 30 October 2026 says annual recurring revenue passed $400M. These figures come from the company and press. Among customer-service platforms such as Zendesk or Intercom, Sierra targets large enterprises; small teams wanting to sign up and start are not its market.
Screenshots
Plans & pricing
Prices last verified Nov 10, 2026
Enterprise (outcome-based)
BusinessContact sales
Sierra publishes no price list. Per its blog post of 10 December 2024, fees are tied to outcomes agreed up front, such as a resolved support conversation, a saved cancellation or an upsell. In most cases unresolved conversations and escalations to humans are not charged. For routing or greeter-style deployments, Sierra may charge per conversation regardless of outcome.
- Free trial
- No free trial
Cancellation & refunds
Sierra's website states no refund policy or trial; terms are set in each customer contract.
Privacy
Sierra's privacy policy covers its websites and the services where Sierra Technologies processes data directly. Collected data includes business contact details, purchase data (payments handled by third-party processors), IP address, device information and approximate location. It says Sierra may 'sell' or 'share' data with analytics and advertising partners as the CCPA defines those terms, with an opt-out for California residents, and that its service providers may supply generative AI services. Retention is described only in general terms (while you use the services or as needed for the stated purposes). The Trust and reliability page says customer data is used only as the customer instructs and never shared with other customers, that personally identifiable information sent to the agent is automatically encrypted and masked, and lists SOC 2, ISO 27001, ISO 42001, HIPAA, GDPR, CCPA, CSA STAR, PCI DSS Level 1 and FedRAMP High. These are vendor statements, not independently verified.
Sierra alternatives
Frequently asked questions
How does Sierra charge?
Per Sierra's blog, fees are tied to outcomes agreed up front, such as a resolved conversation; some deployments such as routing may be billed per conversation. Sierra publishes no specific rates.
Does Sierra have a free plan or trial?
Sierra's website mentions neither a free plan nor a trial. It sells to enterprises through its sales team.
Which channels does Sierra support?
The homepage lists chat, SMS, WhatsApp, email, voice and ChatGPT, with one agent shared across them.
What security certifications does Sierra list?
The Trust and reliability page lists SOC 2, HIPAA, GDPR, PCI DSS Level 1, FedRAMP High, CCPA, CSA STAR, ISO 27001 and ISO 42001. These are Sierra's own statements; ask for the audit reports when buying.
Review evidence & sources8
Scores
- Ease of use
- 7.0
- Features
- 8.0
- Value for money
- 6.5
- Performance
- 7.0
- Support
- 6.5
- Privacy & security
- 6.5
Why this score
Sierra says Agent Studio and Ghostwriter build agents from plain-language descriptions, with or without engineers. The interface is English-only. No independent user reviews confirm this.
Why this score
Per the homepage and blog: multichannel including voice, conversation analytics, monitoring, experiments, long-running agents (Horizon) and a Compliance Console.
Why this score
Outcome pricing lowers buyer risk, but with no public prices it is hard to compare; SalesforceBen notes that defining a successful outcome is ambiguous.
Why this score
CMSWire cites deployments such as Singtel resolving over 70% of conversations, but these are company-supplied figures. With no independent measurements, the score stays moderate.
Why this score
Sold under enterprise contracts; the website describes no specific support channels or service levels.
Why this score
The Trust page lists many certifications and per-customer data separation, but the privacy policy says data may be 'sold' or 'shared' with advertising partners and gives no specific retention periods.
Sources
- Vendor-providedOfficial homepageNov 10, 2026
- Vendor-providedOfficial trust and reliability pageNov 10, 2026
- Vendor-providedOfficial privacy policyNov 10, 2026
- Vendor-providedSierra blog: outcome-based pricing (2024-12-10)Nov 10, 2026
- Vendor-providedSierra blog indexNov 10, 2026
- Vendor-providedSierra blog: HorizonNov 10, 2026
- pressCMSWire (2026-05)Nov 10, 2026
- pressSalesforceBen (2026-08-03)Nov 10, 2026
Specs & compatibility
Change history
- Company.Sierra says annual recurring revenue passed $400M.
- Feature.Horizon launched for agents pursuing long-running goals.
- Company.CMSWire reports Sierra raised $950M led by Tiger Global and GV at a valuation above $15B.
Full change history (6)
- Feature.Agent OS 2.0 and Agent Data Platform unveiled at Sierra Summit 2025.
- Price.Sierra publishes its post on outcome-based pricing.
- Launch.Sierra launched (per CMSWire, month only).
About the author
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