Sierra vs Zendesk AI Comparison
Compare Sierra vs Zendesk AI features, pricing, and more.
Last updated: November 2026
Sierra
7.4/10
Sierra is an enterprise conversational AI platform that builds and runs customer service agents across chat, voice, SMS, WhatsApp and email.
Zendesk AI
6.6/10
Zendesk AI is the AI layer of the Zendesk customer service platform, with AI agents, an agent Copilot, triage and knowledge tools for support teams.
Feature-by-Feature Comparison
| Feature | | |
|---|---|---|
| Scores | ||
| Overall Rating | 7.4/10 | 6.6/10 |
| Analytics | 8/10 | 7/10 |
| Cost | 2/10 | 3/10 |
| Customization | 9/10 | 7/10 |
| Ease of Use | 7/10 | 6/10 |
| Integration | 8/10 | 9/10 |
| Output Quality | 9/10 | 7/10 |
| Scalability | 9/10 | 9/10 |
| Security | 9/10 | 8/10 |
| Support | 8/10 | 5/10 |
| Pricing | ||
| Free plan | No | No |
| Cheapest paid plan | Contact for pricing | $25/user/mo Support Team |
| Estimated cost for 10 users | Contact for pricing | $250/mo Support Team |
| Features | ||
| AI Agents | ||
| Chatbots | ||
| Enterprise Controls | ||
| Knowledge Base Search | ||
| Text Generation | ||
| Voice and Audio | ||
| Workflow Automation | ||
| Transcription | Not listed | |
Sierra vs Zendesk AI cost by team size
| Team size | Sierra | Zendesk AI |
|---|---|---|
| 1 user | Contact for pricing | $25/moSupport Team |
| 5 users | Contact for pricing | $125/moSupport Team |
| 10 users | Contact for pricing | $250/moSupport Team |
| 25 users | Contact for pricing | $625/moSupport Team |
| 50 users | Contact for pricing | $1,250/moSupport Team |
The plan that fits each team size, billed monthly, before add-ons and usage charges. Each cost opens that tool's pricing calculator for the team size.
Which One Should You Choose?
Why choose Sierra
- Higher Support score (8/10 vs 5/10)
- Higher Customization score (9/10 vs 7/10)
- Better fit for enterprise (10/10 vs 8/10)
Why choose Zendesk AI
- Higher Cost score (3/10 vs 2/10)
- Higher Integration score (9/10 vs 8/10)
- Better fit for small business (5/10 vs 1/10)
- Better fit for mid-market (8/10 vs 5/10)
Pros & Cons
Sierra
Pros
- Outcome-based billing means customers usually pay only for resolved conversations or other agreed results, not for each seat.
- Three build options cover both CX teams and engineers: the no-code Agent Studio, the code-first Agent SDK, and Ghostwriter for building agents from SOPs.
- One agent runs across chat, voice, SMS, WhatsApp, email and ChatGPT, keeping context between channels.
- Its list of compliance attestations is broad, covering SOC 2, ISO 27001, ISO 42001, HIPAA, PCI DSS and FedRAMP.
- It has a strong roster of enterprise customers, including SiriusXM, ADT, Rocket Mortgage and SoFi.
Cons
- There is no public pricing, and competitor estimates put annual contracts at about $150,000 or more.
- There is no self-serve or trial tier, so small teams cannot try it on their own.
- Implementation is largely vendor-led, which can make customers depend on Sierra's team for changes.
- There are few public reviews (7 on Gartner Peer Insights) to verify claims against.
- Some reviewers say voice quality still falls short of human level, and that complex telephony setups depend on how far the integration goes.
Zendesk AI
Pros
- You pay only for verified automated resolutions; handoffs to human agents are not charged.
- AI agents work across messaging, email and voice, and support about 80 text languages and 53 voice languages.
- Prebuilt actions connect to Salesforce, Shopify, Jira, HubSpot and Stripe.
- Reviewers on G2 and Capterra praise AI ticket summaries, triage and routing.
Cons
- Total cost adds up from seats, the $50 Copilot add-on, per-resolution fees and action credits.
- AI agents are configured in a separate workspace, and each channel needs its own agent.
- Complex multi-step procedures may need expert help, and Suite Professional has no sandbox for testing changes.
- Frequent changes to the AI agent lineup are retiring older agent types and force migrations.
- G2 reviewers complain about long waits for Zendesk's own customer support.
Not sold on either?
Frequently Asked Questions
Sierra scores higher on our AI Software criteria: 7.4/10 against 6.6/10 for Zendesk AI. The largest gap is in Support: 8/10 for Sierra and 5/10 for Zendesk AI.
No, neither Sierra nor Zendesk AI lists a free plan.
Zendesk AI is the better fit for small business: we rate it 5/10 for them, against 1/10 for Sierra.
