Decagon vs Sierra Comparison
Compare Decagon vs Sierra features, pricing, and more.
Last updated: November 2026
Decagon
6.9/10
Decagon is an enterprise platform for AI customer service agents that resolve support conversations over chat, email and voice.
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.
Feature-by-Feature Comparison
| Feature | | |
|---|---|---|
| Scores | ||
| Overall Rating | 6.9/10 | 7.4/10 |
| Analytics | 8/10 | 8/10 |
| Cost | 3/10 | 2/10 |
| Customization | 8/10 | 9/10 |
| Ease of Use | 6/10 | 7/10 |
| Integration | 7/10 | 8/10 |
| Output Quality | 8/10 | 9/10 |
| Scalability | 9/10 | 9/10 |
| Security | 8/10 | 9/10 |
| Support | 8/10 | 8/10 |
| Pricing | ||
| Free plan | No | No |
| Cheapest paid plan | Contact for pricing | Contact for pricing |
| Estimated cost for 10 users | Contact for pricing | Contact for pricing |
| Features | ||
| AI Agents | ||
| Chatbots | ||
| Knowledge Base Search | ||
| Text Generation | ||
| Voice and Audio | ||
| Workflow Automation | ||
| Custom Model Training | Not listed | |
| Enterprise Controls | Not listed | |
Which One Should You Choose?
Why choose Decagon
- Higher Cost score (3/10 vs 2/10)
Why choose Sierra
- Higher Customization score (9/10 vs 8/10)
- Higher Ease of Use score (7/10 vs 6/10)
Pros & Cons
Decagon
Pros
- Chat, email and voice agents run on one shared intelligence layer, so behaviour stays consistent across channels.
- Agent workflows are written as natural-language AOPs, so support operations staff can define multi-step actions such as refunds.
- Built-in A/B experiments, simulation testing and Watchtower QA support ongoing tuning at scale.
- Large reference customers report results, for example 70% chat and voice resolution at Chime and an 80% deflection rate at Duolingo.
- Reviewers on G2 rate it highly, with an average around 4.9 out of 5, and praise how quickly support responds.
Cons
- There is no public pricing, so every quote needs a sales call.
- Under per-conversation billing you pay even when the AI fails to resolve an issue.
- Reviewers report an average implementation time of about two months.
- Third parties describe helpdesk integrations as API-based rather than marketplace apps, and some reviewers mention missing features.
- It is not suited to startups or small businesses.
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.
Not sold on either?
Frequently Asked Questions
Sierra scores higher on our AI Software criteria: 7.4/10 against 6.9/10 for Decagon. The largest gap is in Cost: 3/10 for Decagon and 2/10 for Sierra.
No, neither Decagon nor Sierra lists a free plan.
