---
pair: polyai-vs-sierra
page_url: https://ai-agent.review/compare/polyai-vs-sierra
record_url: https://ai-agent.review/compare/polyai-vs-sierra.md
agents: [polyai, sierra]
tested_performance: not-yet-tested
facts_checked_at: 2026-09-20
---

# PolyAI vs Sierra

Comparing **PolyAI** (PolyAI, https://ai-agent.review/agents/polyai.md) and **Sierra** (Sierra, https://ai-agent.review/agents/sierra.md).

Source-based review. This portal has not run a hands-on benchmark, so nothing here reports observed performance. No record contains a score, a rating or a benchmark result, and none will until the agents have actually been tested.

Facts last checked 20 Sept 2026, the earlier of the two records.

## Fit comparison

Each state describes what the reviewed sources establish about a workflow, not whether the product is good at it. Vendor-documented means the vendor documents the workflow. External report means a source outside the vendor discusses it. Caveat documented means a cited source describes a limitation or failure in a specific context; read it alongside any capability evidence. Not established means the reviewed sources do not settle it, which is not the same as the product being unable to do it. States are derived from the cited claims below, never stored.

| Area | PolyAI | Sierra |
| --- | --- | --- |
| Billing | External report | Vendor-documented |
| Orders | External report | Vendor-documented |
| Returns | Not established | Vendor-documented |
| Product questions | Vendor-documented | Vendor-documented |
| Account issues | Not established | Vendor-documented |
| Complaints | Caveat documented | Vendor-documented |
| Human handoff | Caveat documented | Vendor-documented |
| Small businesses | Not established | Not established |
| Mid-market | Not established | Not established |
| Enterprise | External report | Vendor-documented |

Evidence for each verdict is listed per agent below.

### PolyAI: fit evidence

### Billing — External report

- **Vendor capability:** PolyAI's integrations page lists "billing & payments" among the functions its agents perform against connected systems. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI — Integrations](https://poly.ai/integrations/); claim id: `polyai-billing-vendor`)_
- **Independent report:** TechCrunch reported that PolyAI's voice assistants complete tasks including payment processing for contact-centre callers. _(Independent report, published 7 Sept 2022, checked 20 Sept 2026; source: [PolyAI lands $40M to handle contact center calls automatically](https://techcrunch.com/2022/09/07/polyai-lands-40m-to-handle-contact-center-calls-automatically/); claim id: `polyai-billing-tc`)_

> PolyAI's own handoff documentation names billing disputes as an example of a conversation the agent escalates to a human rather than resolving.

### Orders — External report

- **Vendor capability:** PolyAI's integrations page lists "order management" and "booking & reservations" among the supported agent functions. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI — Integrations](https://poly.ai/integrations/); claim id: `polyai-orders-vendor`)_
- **Independent report:** TechCrunch reported that PolyAI's system handles order status updates and reservation management on inbound calls. _(Independent report, published 7 Sept 2022, checked 20 Sept 2026; source: [PolyAI lands $40M to handle contact center calls automatically](https://techcrunch.com/2022/09/07/polyai-lands-40m-to-handle-contact-center-calls-automatically/); claim id: `polyai-orders-tc`)_

### Returns — Not established

No public source was found that settles this.

### Product questions — Vendor-documented

- **Vendor capability:** PolyAI documents curated FAQ topics, retrieval-augmented generation, and external knowledge sources ingested from URLs, files (PDF, Office, CSV, JSON, HTML and others) and helpdesk knowledge bases. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI Docs — Knowledge sources introduction](https://docs.poly.ai/knowledge/sources/introduction.md); claim id: `polyai-knowledge-vendor`)_

> URL ingestion is documented as limited to one level below the starting URL and a maximum of ten embedded pages, and the Zendesk and Gladly knowledge syncs are marked beta. Those constrain one ingestion route rather than the capability itself, so they are recorded here rather than as a gap. No independent evidence of answer quality was found, so the verdict stays unknown.

### Account issues — Not established

No public source was found that settles this.

### Complaints — Caveat documented

- **Documented gap:** PolyAI's handoff documentation names complaints, alongside billing disputes and out-of-scope requests, as the conversation types where the agent escalates to a human rather than resolving autonomously. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI Docs — Voice channel: Handoffs](https://docs.poly.ai/voice-channel/handoffs.md); claim id: `polyai-complaints-gap`)_

### Human handoff — Caveat documented

- **Vendor capability:** PolyAI documents voice handoff via SIP REFER, SIP INVITE or SIP BYE with escalation context passed through custom X- SIP headers, a Handoff State API endpoint and a Conversations API transcript, plus chat handoff integrations for Salesforce, Zendesk, NICE CXone, Amazon Connect, Webex and Five9. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI Docs — Voice channel: Handoffs](https://docs.poly.ai/voice-channel/handoffs.md); claim id: `polyai-handoff-vendor`)_
- **Documented gap:** PolyAI's handoff documentation states that with the default SIP REFER method "the utterance may not play before the transfer completes because the REFER fires at the same time as function execution", and that inbound SIP voicemail detection on the destination side is "not available by default" for SIP REFER, BYE or INVITE transfers. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI Docs — Voice channel: Handoffs](https://docs.poly.ai/voice-channel/handoffs.md); claim id: `polyai-handoff-gap`)_

### Small businesses — Not established

No public source was found that settles this.

### Mid-market — Not established

No public source was found that settles this.

### Enterprise — External report

- **Vendor capability:** PolyAI positions itself as an enterprise-scale agentic dialog platform and markets to nine industries: consumer services, financial services, healthcare, hotels, insurance, restaurants, retail, telecom and utilities. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI homepage](https://poly.ai/); claim id: `polyai-enterprise-vendor`)_
- **Independent report:** CX Today reports PolyAI was placed in the 2025 Gartner Magic Quadrant for Conversational AI Platforms as a Niche Player, with Gartner highlighting its low customer churn and research investment. _(Independent report, published 19 Aug 2025, checked 20 Sept 2026; source: [Gartner Magic Quadrant for Conversational AI Platforms 2025: The Rundown](https://www.cxtoday.com/customer-analytics-intelligence/gartner-magic-quadrant-for-conversational-ai-platforms-2025-the-rundown/); claim id: `polyai-enterprise-gartner`)_
- **Independent report:** TechCrunch reported PolyAI's customers included FedEx and Marriott alongside dozens of enterprise and government clients handling millions of interactions monthly. _(Independent report, published 7 Sept 2022, checked 20 Sept 2026; source: [PolyAI lands $40M to handle contact center calls automatically](https://techcrunch.com/2022/09/07/polyai-lands-40m-to-handle-contact-center-calls-automatically/); claim id: `polyai-enterprise-tc-customers`)_

> Gartner's cautions in the same analysis concern inflexible consumption-based pricing and an immature channel partner network.

### Sierra: fit evidence

### Billing — Vendor-documented

- **Vendor capability:** Sierra’s AOL case study describes explanations of outstanding balances, billing history and payment-method updates. The example is AOL’s configured agent, not a guarantee that every Sierra deployment includes billing access. _(Vendor-reported, checked 20 Sept 2026; source: [AOL customer story (Sierra)](https://sierra.ai/customers/aol); claim id: `sierra-billing-aol`)_

> Illustrative evaluation: ask why a subscription charge increased, then request a card update. Verify identity checks, the source of the billing explanation and the permitted update path.

### Orders — Vendor-documented

- **Vendor capability:** Sierra’s Minted case study describes order updates across design approval, printing and shipping, plus priority-shipping changes for delayed orders. This supports an order-management use case in that deployment. _(Vendor-reported, checked 20 Sept 2026; source: [Minted customer story (Sierra)](https://sierra.ai/customers/minted); claim id: `sierra-orders-minted`)_

> Illustrative evaluation: use a split shipment with one delayed item. Require the agent to distinguish production status from carrier status and avoid promising a delivery date that the connected system does not provide.

### Returns — Vendor-documented

- **Vendor capability:** Sierra’s retail page lists refund requests and exchanges among supported workflows. It does not specify a universal return-policy configuration or prove that a particular refund reaches the payment processor. _(Vendor-reported, checked 20 Sept 2026; source: [Retail and consumer goods (Sierra)](https://sierra.ai/industries/retail); claim id: `sierra-returns-retail-exchanges`)_

> Illustrative evaluation: request an exchange for an item outside the normal return window. Check the configured exception policy, approval requirement and final state in the order system.

### Product questions — Vendor-documented

- **Vendor capability:** Sierra describes grounding answers in company knowledge, policies and brand guidance. That provides a route to product answers based on supplied content; it does not establish accuracy for a buyer’s catalog. _(Vendor-reported, checked 20 Sept 2026; source: [Meet your agent (Sierra)](https://sierra.ai/product/meet-your-agent); claim id: `sierra-productq-meet-knowledge`)_

> Illustrative evaluation: ask whether an accessory works with an older product model. Supply an approved compatibility source and check that missing information leads to clarification rather than an invented answer.

### Account issues — Vendor-documented

- **Vendor capability:** Sierra’s Ramp case study describes card locking and replacement, address validation and transaction explanations. These are account actions in Ramp’s configured implementation; password recovery and other account workflows require their own evidence. _(Vendor-reported, checked 20 Sept 2026; source: [Ramp customer story (Sierra)](https://sierra.ai/customers/ramp); claim id: `sierra-account-ramp`)_

> Illustrative evaluation: an authenticated cardholder requests a replacement card and address change. Check permissions, address confirmation and the resulting card state before considering the journey complete.

### Complaints — Vendor-documented

- **Vendor capability:** Sierra says its agents can recognize frustration and adapt their responses. This is a vendor claim about conversational behavior, not a measured result for complaint resolution or customer satisfaction. _(Vendor-reported, checked 20 Sept 2026; source: [Meet your agent (Sierra)](https://sierra.ai/product/meet-your-agent); claim id: `sierra-complaints-meet-frustration`)_

> Illustrative evaluation: a customer repeats a cancellation request after rejecting a retention offer. Check that the configured flow respects the refusal and provides the agreed cancellation or human-escalation path.

### Human handoff — Vendor-documented

- **Vendor capability:** Sierra’s SDK page documents routing an escalated conversation to a team member with a generated summary. It does not establish how quickly a human answers in a particular contact center. _(Vendor-reported, checked 20 Sept 2026; source: [Agent SDK (Sierra)](https://sierra.ai/product/agent-sdk); claim id: `sierra-handoff-sdk`)_

> Illustrative evaluation: request a person during a failed account update. Check queue routing, transcript and summary delivery, plus what the customer sees when the team is offline.

### Small businesses — Not established

No public source was found that settles this.

> Business size alone does not establish suitability. Illustrative buying scenario: a small team needs one FAQ channel; ask for the implementation work and ongoing maintenance required for that scope before deciding whether the platform is proportionate.

### Mid-market — Not established

No public source was found that settles this.

> The reviewed sources do not establish a universal mid-market fit. Illustrative buying scenario: a growing retailer needs order support across two brands; evaluate connector coverage, ownership of policy updates and support capacity for that deployment.

### Enterprise — Vendor-documented

- **Vendor capability:** Sierra publishes customer stories for AOL, Minted and Ramp, including connected service workflows. These are vendor-published deployment examples, not proof that every enterprise requirement is met. _(Vendor-reported, checked 20 Sept 2026; source: [Customer stories and examples (Sierra)](https://sierra.ai/); claim id: `sierra-enterprise-vendor`)_

> Illustrative buying scenario: multiple business units need separate permissions and policies. Request a demonstration using those boundaries and review the operational and security requirements of the proposed deployment.

## Product information

| Attribute | PolyAI | Sierra |
| --- | --- | --- |
| Deployment model | PolyAI states its service is hosted on AWS, that the company is ISO 27001-certified and aligned with National Cyber Security Centre guidelines; it publishes Sandbox, Staging and Live environments with API-driven publishing, and no self-hosted option is documented. (Vendor-reported, checked 20 Sept 2026) | Sierra documents configuration through Agent Studio and custom integrations for proprietary systems. Deployment work includes defining journeys and connecting the systems those journeys use. (Vendor-reported, checked 20 Sept 2026) |
| Channels | PolyAI is voice-first — its documentation calls it an "enterprise platform for building voice and chat agents" and its pricing is per minute of voice-agent use — with secondary documented channels covering web chat, SMS and RCS, email, and iOS/Android SDKs (including in-app voice calling). (Vendor-reported, checked 20 Sept 2026) | Vendor-listed channels include phone, website and app chat, WhatsApp, Apple Business Chat, SMS and email. Live Assist supports staff, and Sierra also documents publishing selected agent journeys to ChatGPT. (Vendor-reported, checked 20 Sept 2026) |
| Languages | PolyAI's languages page claims "75+ languages with native fluency" and lists 42 by name, while its developer documentation homepage states 24+ languages. (Vendor-reported, checked 20 Sept 2026) | The current Channels page describes voice models tuned for 60+ locales. A locale is not the same as a language; verify the exact language, accent and channel required for your deployment. (Vendor-reported, checked 20 Sept 2026) |
| Help desk and CRM integrations | PolyAI documents integrations with Salesforce (customer lookup and case management), Zendesk (Talk voice routing and ticketing), Gladly, NICE CXone, Amazon Connect, Webex, Five9 and Twilio, and its marketing site claims "130+ integrations available" across telephony/voice routing, CRM and knowledge, productivity, and vertical systems. (Vendor-reported, checked 20 Sept 2026) | Agent Studio lists 40+ prebuilt integrations for knowledge, systems of record and contact centers, but this page does not identify the help-desk connectors. Confirm your help desk and required handoff behavior with Sierra. (Vendor-reported, checked 20 Sept 2026) |
| Knowledge sources | PolyAI combines curated FAQ topics with RAG over external sources — scraped URLs, uploaded files (PDF, DOCX, XLSX, PPTX, CSV, JSON, XML, MD, HTML, EML, EPUB and more) and beta syncs from Zendesk Help Center and Gladly — chunked at 2000 characters with 500-character overlap. (Vendor-reported, checked 20 Sept 2026) | The SDK documents ingestion of company FAQs, policies and documentation into its knowledge engine. (Vendor-reported, checked 20 Sept 2026) |
| Actions in backend systems | PolyAI states its agents perform account management, authentication, call routing, billing and payments, booking and reservations, order management, troubleshooting and FAQ against integrated systems, with custom connectors documented alongside telephony, CRM and payments integrations. (Vendor-reported, checked 20 Sept 2026) | The SDK lists subscription updates and warranty submissions as examples of actions through connected systems. Required permissions and workflow configuration depend on the implementation. (Vendor-reported, checked 20 Sept 2026) |
| Human handoff | PolyAI documents that the agent "runs autonomously by default and escalates to a human only when needed", transferring calls via SIP REFER, SIP INVITE or SIP BYE and passing customer ID, verification status, escalation reason and transcript through SIP headers and the Handoff and Conversations APIs. (Vendor-reported, checked 20 Sept 2026) | The SDK documents routing to a team member with an automatic conversation summary. (Vendor-reported, checked 20 Sept 2026) |
| Target customer size | PolyAI targets enterprise contact centres across nine industries and sells via demo request, with ongoing use "priced on a per-minute basis, which includes proactive performance improvements, maintenance and 24/7 support" and no published price points or free tier. (Vendor-reported, checked 20 Sept 2026) | Sierra’s public customer examples include AOL, Minted and Ramp. These show deployments in established businesses; they do not define a minimum viable team size. (Vendor-reported, checked 20 Sept 2026) |
| Vendor-reported performance claims | Unknown | Sierra reports 90% case resolution at Ramp. This is a vendor-published customer result with no common benchmark population supplied here; it should not be compared directly with another vendor’s deflection or resolution figure. (Vendor-reported, checked 20 Sept 2026) |

Full source links for each attribute are in the per-agent records linked above.

## Industry comparison

An industry state says where the cited sources place the product, not how well it performed there. The same four states and the same rubric apply. Industry entries cite claims published in the agent's own record, by id, so a source is never stored twice and the two copies can never disagree. An industry with no entry is unknown, which is a gap in the public record rather than a finding.

| Industry | PolyAI | Sierra |
| --- | --- | --- |
| Retail and e-commerce | Vendor-documented | Vendor-documented |
| Financial services | Vendor-documented | Not established |
| Telecommunications | Vendor-documented | Not established |
| Travel and hospitality | External report | Not established |
| Healthcare | Vendor-documented | Not established |
| Public sector and education | External report | Not established |
| Logistics and delivery | External report | Not established |

Evidence for each industry is listed per agent below.

### PolyAI: industry evidence

### Retail and e-commerce — Vendor-documented

- PolyAI positions itself as an enterprise-scale agentic dialog platform and markets to nine industries: consumer services, financial services, healthcare, hotels, insurance, restaurants, retail, telecom and utilities. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI homepage](https://poly.ai/); claim id: `polyai-enterprise-vendor`)_

> Retail and restaurants are among the marketed verticals. The claim is the vendor's positioning of the product.

### Financial services — Vendor-documented

- PolyAI positions itself as an enterprise-scale agentic dialog platform and markets to nine industries: consumer services, financial services, healthcare, hotels, insurance, restaurants, retail, telecom and utilities. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI homepage](https://poly.ai/); claim id: `polyai-enterprise-vendor`)_

> Financial services and insurance appear in the nine industries PolyAI markets to. A marketed vertical is a statement of intent, not evidence of a deployment.

### Telecommunications — Vendor-documented

- PolyAI positions itself as an enterprise-scale agentic dialog platform and markets to nine industries: consumer services, financial services, healthcare, hotels, insurance, restaurants, retail, telecom and utilities. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI homepage](https://poly.ai/); claim id: `polyai-enterprise-vendor`)_

> Telecom is one of the nine marketed industries, sourced to PolyAI's own homepage.

### Travel and hospitality — External report

- PolyAI positions itself as an enterprise-scale agentic dialog platform and markets to nine industries: consumer services, financial services, healthcare, hotels, insurance, restaurants, retail, telecom and utilities. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI homepage](https://poly.ai/); claim id: `polyai-enterprise-vendor`)_
- TechCrunch reported PolyAI's customers included FedEx and Marriott alongside dozens of enterprise and government clients handling millions of interactions monthly. _(Independent report, published 7 Sept 2022, checked 20 Sept 2026; source: [PolyAI lands $40M to handle contact center calls automatically](https://techcrunch.com/2022/09/07/polyai-lands-40m-to-handle-contact-center-calls-automatically/); claim id: `polyai-enterprise-tc-customers`)_

> Hotels are a marketed vertical, and TechCrunch separately named Marriott among the customers. The report names the account; it does not describe what the agent handles there.

### Healthcare — Vendor-documented

- PolyAI positions itself as an enterprise-scale agentic dialog platform and markets to nine industries: consumer services, financial services, healthcare, hotels, insurance, restaurants, retail, telecom and utilities. _(Vendor-reported, checked 20 Sept 2026; source: [PolyAI homepage](https://poly.ai/); claim id: `polyai-enterprise-vendor`)_

> Healthcare is one of the nine industries on PolyAI's own homepage. No healthcare deployment is independently reported.

### Public sector and education — External report

- TechCrunch reported PolyAI's customers included FedEx and Marriott alongside dozens of enterprise and government clients handling millions of interactions monthly. _(Independent report, published 7 Sept 2022, checked 20 Sept 2026; source: [PolyAI lands $40M to handle contact center calls automatically](https://techcrunch.com/2022/09/07/polyai-lands-40m-to-handle-contact-center-calls-automatically/); claim id: `polyai-enterprise-tc-customers`)_

> The same TechCrunch report refers to dozens of enterprise and government clients. Government clients are counted, not named or described.

### Logistics and delivery — External report

- TechCrunch reported PolyAI's customers included FedEx and Marriott alongside dozens of enterprise and government clients handling millions of interactions monthly. _(Independent report, published 7 Sept 2022, checked 20 Sept 2026; source: [PolyAI lands $40M to handle contact center calls automatically](https://techcrunch.com/2022/09/07/polyai-lands-40m-to-handle-contact-center-calls-automatically/); claim id: `polyai-enterprise-tc-customers`)_

> TechCrunch named FedEx among PolyAI's customers. A named account in funding coverage, with no description of the workflows in use.

### Sierra: industry evidence

### Retail and e-commerce — Vendor-documented

- Sierra’s retail page lists refund requests and exchanges among supported workflows. It does not specify a universal return-policy configuration or prove that a particular refund reaches the payment processor. _(Vendor-reported, checked 20 Sept 2026; source: [Retail and consumer goods (Sierra)](https://sierra.ai/industries/retail); claim id: `sierra-returns-retail-exchanges`)_

> Sierra's retail and consumer goods page lists refunds and exchanges among supported workflows. Vendor documentation only; no retail deployment is independently reported.

### Financial services — Not established

No reviewed source places this product in this industry.

### Telecommunications — Not established

No reviewed source places this product in this industry.

### Travel and hospitality — Not established

No reviewed source places this product in this industry.

### Healthcare — Not established

No reviewed source places this product in this industry.

### Public sector and education — Not established

No reviewed source places this product in this industry.

### Logistics and delivery — Not established

No reviewed source places this product in this industry.

## PolyAI: evidence base

The independent evidence behind these states comes mainly from analysts and trade press.

Independent sources behind these verdicts: cxtoday.com, techcrunch.com.
By kind: analysts and trade press (4).

Verdicts across agents are not directly comparable while the evidence behind them comes from different
kinds of source. See https://ai-agent.review/methodology#evidence-asymmetry.

## Sierra: evidence base

No independent source has been found for any fit area, so every state here rests on vendor material or nothing.

Independent sources behind these verdicts: none.

Verdicts across agents are not directly comparable while the evidence behind them comes from different
kinds of source. See https://ai-agent.review/methodology#evidence-asymmetry.

## Corrections

Factual corrections with a public source are accepted at corrections@ai-agent.review and answered within 14 days. Method: https://ai-agent.review/methodology