Sierra vs Yellow.ai (2026): which should you pick?
As of Nov 12, 2026, Yellow.ai grades higher than Sierra: 2.2 against 1.6 out of 4.0.
Checked Nov 12, 2026 · graded Nov 12, 2026 by ToolGPA
Yellow.ai grades higher on the free plan and platforms. They get the same grade on value for money, features and ease of use.
Price, platforms and features side by side. The table says where each price was read and when.
Which one is for you
Pick Sierra if
- Fits if you are a large brand with heavy customer service volume
- Makes sense if you want to pay by outcome rather than seat
Look elsewhere if
- Not for you if you want a price, as none is published
- Not for you if you want to try it, since there is no self-serve sign-up or free plan
- Skip it if you are small, because the site is aimed at large brands
- Watch out: no integrations are listed, so ask what it connects to
Pick Yellow.ai if
- Fits if you want to try one service agent free
- Makes sense if you want to pay per resolution rather than per seat
Look elsewhere if
- Tight if you grow, as Free is 1 agent and 500 sessions a month
- Pricey if volume is high, since extra resolutions are $0.99 each
- Watch out: the Free plan lists many features as limited
- Not for you if you want Enterprise prices, because they are not published
How we grade them
| 1.6GPASierraWeak | 2.2GPAYellow.aiFair | |
|---|---|---|
| Value for money | CNo price is published; the site says pricing is outcome-based and points to a sales call. | CFree, then $0.99 per resolution after 500 sessions, with Enterprise custom. There is no published paid plan to compare. |
| Free plan and trial | FNo free plan and no sign-up. The route is a sales conversation. | CFree is 1 AI agent and 500 sessions a month with limited channels, integrations and analytics. You will hit the caps. |
| Features | CAn agent builder, channels, insights and observability are listed, but nothing in the listing says how far each goes. | CBuilder, voice and email, copilot, testing and analytics. The Free plan lists many features as limited, with 1,000 user records and one active campaign. |
| Ease of use | CNo store rating on record, and a large brand has to onboard it with the vendor. | CNo store rating on record, and you build and connect an agent before it answers. |
| Platforms and integrations | CWeb only, and the site lists no integrations. | BWeb, with Zendesk, Freshdesk, HubSpot and Genesys listed, and 35+ channels and 150+ integrations on Enterprise. |
| Best for | big consumer brands buying a service agent from the vendor | trying one service agent before an enterprise deal |
The GPA is the average of the five grades: an A is 4 points, an F is none. The full reasons are on each tool's page: Sierra and Yellow.ai. How we grade
Where they differ
- Yellow.ai also covers workflow automation.
In commonWebAI agentsAI support agentChatbots
At a glance
| Sierra | Yellow.ai | |
|---|---|---|
| Pricing | Paid | Free plan |
| Starts at | Not published | Not published |
| Free plan | None | 1 AI agent, 500 chat sessions a month, then $0.99 per resolution, with limited features. |
| Free trial | None listed | None listed |
| Web | ||
| Made by | Sierra | Yellow.ai |
| Price read from | Not confirmed | yellow.ai |
| Checked | Nov 12, 2026 | Nov 12, 2026 |
Worth knowing
Sierra
- No prices are published; Sierra says pricing is outcome-based and points visitors to a sales conversation.
- No self-serve sign-up or free plan is shown on the site.
- The site gives no list of integrations.
Yellow.ai
- The Free plan lists many features as limited, and extra resolutions cost $0.99 each.
- Enterprise pricing is not published.
- The Free plan table lists 1,000 user records and one active campaign with 10 templates.
Key features
Sierra
- Ghostwriter agent builder
- Builds an agent from uploaded SOPs, transcripts and recordings or a plain-English description, with guardrails and multilingual support.
- Channels
- A single agent can be deployed on chat, SMS, WhatsApp, email, voice and ChatGPT.
- Insights
- Explorer analyzes conversations, Monitors flags the ones that need attention, and Experiments runs multivariate tests.
- Observability
- Shows each agent action, including tool calls and knowledge lookups, along with latency.
- Horizon
- Plans multi-step outcomes over days or months, using memory of the customer across conversations and systems.
Yellow.ai
- AI Agent Builder
- Builds agents for any channel, with a conversational knowledge base using retrieval over company content.
- Voice and email
- Nexus VOX is its voice product, offering call agents in more than 500 languages, and email agents are a separate feature.
- AI Copilot and testing
- Previews, debugs and optimizes agent performance, with automated testing before release.
- Analytics
- LLM analytics, sentiment and topic tracking, and custom dashboards.
- Employee experience
- Nexus EDGE is a desktop agent for employee experience, with human approval on every action.
Plans
Sierra
Pricing could not be confirmed. See sierra.ai.
Yellow.ai
Free$0
1 AI agent and 500 sessions a month, then $0.99 per resolution. Limited channels, integrations and analytics.
EnterpriseCustom
Unlimited agents and sessions, all 35+ channels, 150+ integrations, SOC 2, GDPR and ISO compliance.
Common questions
Which is cheaper, Sierra or Yellow.ai?
As of Nov 12, 2026, Sierra has no price we could confirm, and Yellow.ai publishes no starting price.
Which has a free plan, Sierra or Yellow.ai?
As of Nov 12, 2026, only Yellow.ai has a free plan. Sierra does not.
More comparisons
How this page was made
- The verdict at the top follows a fixed rule. When both tools are in the same category and either is in our top three for it, the verdict follows that ranking: the higher-placed tool is our pick. The top three weigh who each tool suits as well as its grades, so a pick can go against the GPA. Otherwise the page does not pick one and says which grades higher: the higher GPA first; on a tie, the one with a free plan, then the one that starts cheaper in dollars a month, counted the same way for both; if they are still level, what the choice depends on.
- The grades are our own, from each tool’s review or report card. The GPA is their average.
- Prices, plans and platforms come from each tool’s listing. The table above says where each price was read and when.
- The differences and the answers to the questions are worked out from those listings.