Short answer: Decagon7.4 out of 10 (7.4/10) edges Intercom Fin7.3 out of 10 (7.3/10) on our scores, and both beat Sierra6.7 out of 10 (6.7/10) overall. But the ranking matters less than the buying path. Fin is the one you can start this week at a published price. Decagon and Sierra are enterprise contracts with no public pricing, no free tier and no self-serve signup.
This comparison is for support leaders choosing an autonomous customer-service agent, not a basic chatbot. All three resolve conversations on their own, hand off to humans and cover voice. They differ in how they are priced, how long they take to deploy and how much control you get. Scores come from the weighted rubric on our methodology page; no vendor influences them.
Quick picks:
- Best overall score: Decagon7.4 out of 10, 7.4. Custom enterprise pricing; third-party contract data (Vendr) puts annual deals at roughly $95K to $590K+.
- Best to start with: Intercom Fin7.3 out of 10, 7.3. $0.99 per resolved conversation, with a $49.50/month standalone minimum.
- Most capable, hardest to buy: Sierra6.7 out of 10, 6.7. Custom pricing, with year-one costs commonly estimated at $200K to $350K+ including setup.
Side by side
| Intercom Fin | Decagon | Sierra | |
|---|---|---|---|
| Overall | 7.3 | 7.4 | 6.7 |
| Capability | 8 | 8 | 9 |
| Ease of use | 7 | 7 | 4 |
| Value | 6 | 6 | 4 |
| Reliability | 8 | 8 | 8 |
| Support & docs | 7 | 8 | 8 |
| Starting price | $49.50/month minimum | Custom | Custom |
| Pricing model | $0.99 per resolution, plus seats if you use Intercom | Per conversation or per resolution (about $1.50 estimated) | Per resolution, plus setup fees |
| Typical deployment | Days to weeks (our estimate for existing Intercom users) | 4 to 12 weeks | 3 to 7 months |
| Channels | Chat, email, voice, images | Chat, email, voice, SMS | Chat, voice, SMS, WhatsApp, email, ChatGPT |
| Self-serve | Yes | No | No |
The three tie on reliability. Sierra wins on capability, and loses badly on ease of use and value, which is what pulls it to third.
Intercom Fin: the one you can actually try
Fin averages a 67% resolution rate across all Intercom customers, and that “across all customers” framing is the most credible resolution figure in this group, because it is not a best-case reference account. It works over your knowledge base and live data, and it can take actions: look up a Shopify order, update a Salesforce record, open a Jira ticket. It supports 45 languages, SOC 2 Type II, HIPAA and GDPR.
Fin also runs standalone on top of Zendesk, Salesforce or HubSpot, so you do not have to move helpdesks. Intercom itself rebranded to Fin in May 2026 and Salesforce announced a roughly $3.6 billion acquisition in June 2026. The $0.99 price was reported unchanged at announcement, but we have not seen Salesforce’s own statement on how pricing evolves after integration, so check before signing a long contract.
Weaknesses:
- Costs scale with success. Every resolution is billed, so high-volume teams routinely see four-figure monthly Fin bills.
- Setup is not trivial. The interface needs real onboarding and does not walk you through workflows.
- Nuanced queries. It struggles when a question is multi-step or phrased far from your documentation.
- Vendor support. Buyers report Intercom’s own first-response times of a week or more.
Decagon: highest deflection, most control for ops teams
Decagon is the highest-scoring of the three. Enterprise customers report 75 to 80% ticket deflection in production, and since March 2026 about 80% of its traffic runs on in-house models fine-tuned on support conversations. Its signature feature is Agent Operating Procedures: plain-language workflow instructions that CX staff can edit without engineering. Watchtower monitors conversations in real time, and a supervisor layer screens answers for hallucinations before customers see them. Notion is a named customer.
It fits large teams on Zendesk, Salesforce or Kustomer, though it also integrates with Intercom. Support and onboarding score 8, thanks to dedicated implementation engineers.
Weaknesses:
- No trial, no public price. Everything runs through sales.
- Heavy implementation. Expect 4 to 12 weeks and ongoing engineering time to maintain integrations.
- Feature gaps. The Agent Assist copilot for human agents works only with Zendesk.
- Niche topics. A unified agent may underperform on highly specialised subjects.
Sierra: the broadest platform, with the highest barrier
Sierra, founded in 2024 by Bret Taylor and Clay Bavor, scores 9 on capability, the highest here. It orchestrates 15+ models from OpenAI, Anthropic and Meta per task with automatic failover, covers the widest channel list (including WhatsApp and ChatGPT) and lets teams build agents in Agent Studio or through an SDK. Expert Answers writes knowledge articles from resolved conversations so the agent improves over time. The company reports more than 40% of the Fortune 50 as customers.
The catch is the price and the time. Estimated setup fees run $50K to $200K, deployments take 3 to 7 months, and the proprietary Agent OS ties your workflows to Sierra’s stack. Those factors explain the 4s for ease of use and value. If you are not a large enterprise with serious voice and omnichannel volume, you are not the target buyer.
Weaknesses:
- Zero self-serve access and no public pricing.
- Long, expensive rollout.
- Lock-in risk from the Agent OS abstraction layer.
How the pricing really compares
All three lean on outcome-based pricing, which is why the cost comparison is hard. Fin publishes $0.99 per resolution. Decagon’s per-resolution rate is estimated at about $1.50 and Sierra’s rate is unpublished; neither figure is a vendor quote. Remember that a headline rate excludes seats, setup fees and integration work. Our AI agent pricing guide explains why, and the best customer support agents ranking shows cheaper options for smaller teams.
A rough sense of scale: 10,000 resolutions a month at $0.99 is about $9,900 a month on Fin before seats. Decagon’s reported minimum contracts sit well above that, which is why Fin is the usual starting point unless you are already at enterprise volume.
Which should you choose?
- If you already use Intercom, or want to pilot within weeks, choose Fin.
- If you want to pay per outcome without a sales process, choose Fin.
- If you are an enterprise on Zendesk or Salesforce and want editable workflows, choose Decagon.
- If you want the strongest observability and QA layer, choose Decagon.
- If you run a global, multichannel operation with voice, SMS and WhatsApp and have a budget to match, choose Sierra.
- If you want the Salesforce-native route, see Agentforce6.5 out of 10 and our report on Salesforce’s job-ready Agentforce agents.
- If none of these fit your size, browse the Customer Support category.
Whichever you pick, run a paid pilot on your own tickets and measure resolution rate and wrong-answer rate yourself. Vendor-reported figures are averages from their best deployments.
Next step
Open the profiles to compare sub-scores and plans: Intercom Fin7.3 out of 10, Decagon7.4 out of 10 and Sierra6.7 out of 10. For a smaller team, start with the best AI customer support agents ranking.
Frequently asked questions
Is Intercom Fin better than Decagon?
On our scores they are nearly level: Decagon 7.4, Fin 7.3. Decagon reports higher deflection at enterprise scale and offers more workflow control. Fin is easier to start, has public pricing and reports a 67% resolution rate across all customers.
How much does Sierra cost?
Sierra does not publish pricing. Third-party estimates put year-one cost at $200K to $350K+ including setup fees of $50K to $200K. Treat these as estimates and ask for a quote.
How much does Decagon cost?
Decagon prices per conversation or per resolution through custom contracts. Vendr data reports annual contracts from $95K to $590K+.
Can small businesses use Fin, Decagon or Sierra?
Fin can work for a smaller team because it has a published price and standalone option. Decagon and Sierra are built for large enterprises and are impractical below mid-market scale.
Which has the best voice support?
All three cover voice. Decagon’s Voice 2.0 reports sub-second latency, and Sierra’s voice sits inside a wider omnichannel platform. We have not tested latency independently, so judge each by a live demo.