comparison · hermes vs retell AI · 2026
Hermes vs Retell AI in 2026: Pricing, Features, Reliability, and Who Each Is Actually Built For
By builders, for builders.
Retell AI and Hermes are not the same category of product, which makes this comparison both easier and more important to get right. Retell gives you an API: a low-level voice agent infrastructure layer that a developer can use to build voice call functionality. Hermes gives you a complete agency operating platform: multi-workspace client management, built-in CRM, outbound campaign engine, white-label portals, and per-workspace billing transparency, all without requiring a developer to run. If you are building a custom voice AI product with engineering resources, Retell is worth evaluating. If you are running an AI voice agency, Retell is a component you would need to assemble around, not a platform you can run a business on.
This comparison is written from Hermes's perspective, so the framing is inherently biased in our favor. Read it with that context. We have tried to be accurate on Retell's capabilities and pricing as of mid-2026. Where we are wrong or where Retell has updated their offering, contact us and we will correct it.
Side-by-side comparison
| Feature | Hermes | Retell AI |
|---|---|---|
| What it is | Agency operating platform (full stack) | Voice AI API infrastructure (engine only) |
| Starter price | $149/mo (3 workspaces, 300 min) | Usage-based, ~$0.07 to $0.13/min + model costs |
| Business price | $399/mo (7 workspaces, 1,000 min) | Usage-based, no workspace concept |
| Agency price | $699/mo (20 workspaces, 2,000 min) | Usage-based at scale |
| Typical total cost at 10 clients | $699 to $1,100/mo (plan + overage) | $1,500 to $2,400+/mo (API + full tool stack + dev) |
| Overage rate | $0.24/min all-in | $0.07 to $0.13/min platform + underlying model costs |
| Multi-workspace client isolation | Yes, native (3/7/20 workspaces) | No, must build yourself |
| White-label demo portal | Yes, CNAME-bound, included | No, must build yourself |
| Built-in CRM | Yes, per workspace | No |
| Outbound campaign engine | Yes, native | Via API + your own orchestration |
| Agency billing management | Per-workspace P&L, native | No, must build with Stripe Connect |
| Developer required? | No | Yes, for anything beyond basic use |
| Infrastructure redundancy | Provider-level redundancy built in | Single-provider; outage history in 2025 to 2026 |
| HIPAA BAA | Business and Agency plans | Enterprise tier only |
| Best for | Agency operators running 3 to 20 clients | Developers building custom voice AI applications |
Best for: Retell
Retell is the right choice if you are a software developer or product team building voice AI as a feature inside an existing product. It offers fine-grained API control over the voice agent layer, supports a range of LLM and TTS providers, and has solid developer documentation. Companies building custom voice AI applications, not agencies running clients, belong on a infrastructure-level tool. Retell's pricing model (usage-based with no workspace or operations overhead) makes sense for that use case.
Retell is also a reasonable starting point for an agency operator who wants to experiment with a single client before committing to a platform. The limitation surfaces at client 3 or 4: you will have built custom infrastructure that you now need to maintain and expand, and the developer time cost will exceed the cost of a purpose-built platform like Hermes.
Best for: Hermes
Hermes is built specifically for AI voice agency operators. If you charge clients monthly recurring fees to deploy and manage voice agents on their behalf, Hermes is the platform designed for that business model. The multi-workspace architecture means each client is fully isolated. The white-label portal means your client never sees the word Hermes. The outbound campaign engine means you can offer outbound sequences, not just inbound answering. The per-workspace P&L means you know your margin on every client without manual reconciliation.
Compare the total cost picture honestly: a 10-client agency on Retell with a full DIY stack is spending $1,500 to $2,400 per month in SaaS fees before developer time. The same agency on Hermes Agency at $699 per month retains an additional $800 to $1,700 per month in gross margin from day one. See also Hermes vs Vapi for a parallel comparison on the other major infrastructure provider, and Retell vs Synthflow for the infrastructure vs enterprise platform comparison.
A note on Retell reliability
Retell has experienced multiple publicly reported outage events in 2025 and 2026, some with impact periods lasting several hours. For a product developer testing a prototype, an outage is inconvenient. For an agency operator whose client depends on inbound calls being answered, a Friday afternoon outage is a support and reputation emergency. Infrastructure reliability is not a minor footnote in the Hermes vs Retell comparison for agency operators. Hermes builds infrastructure-level redundancy into the platform so that single-provider events do not directly impact client call handling. According to Retell's public status page, you can review their historical uptime if you want to evaluate this directly.
FAQ
What is Retell AI?
Retell AI is a voice AI infrastructure provider. It gives developers access to conversational voice agent APIs: you define agent configurations, connect LLM and voice model providers, and Retell handles the telephony layer and conversation management. As of mid-2026, Retell charges approximately $0.07 to $0.13 per minute in platform fees on top of underlying LLM and TTS costs, putting total per-minute costs in the $0.13 to $0.30 range depending on model selection. Retell has developer-friendly documentation, good latency characteristics at the infrastructure layer, and solid uptime (though it has experienced notable outages in 2025 to 2026). What Retell does not have: a native multi-workspace agency dashboard, white-label client portals, a built-in CRM, outbound campaign orchestration, per-client billing transparency, or agency operations tooling of any kind. It is voice AI infrastructure, not an agency platform.
What is Hermes?
Hermes is the operating platform for AI voice agencies. It provides everything an agency needs to deploy, manage, and scale voice agent clients under their own brand: per-workspace client isolation, built-in CRM and contact management, outbound campaign engine, white-label demo and management portals at your own CNAME, and per-workspace billing so you can see your margin per client at a glance. Hermes is built on top of voice AI infrastructure (including infrastructure providers like Retell and VAPI) and adds the entire agency operations layer on top. Starter plan is $149 per month (3 workspaces, 300 included minutes). Business is $399 per month (7 workspaces, 1,000 minutes). Agency is $699 per month (20 workspaces, 2,000 minutes). Overage is $0.24 per minute. No developer required to run a full agency on Hermes.
What does a full Retell-based agency stack actually cost?
An agency operator trying to build the equivalent of Hermes on top of Retell needs to assemble and maintain: Retell API access (usage-based costs), a CRM like GoHighLevel ($97 to $497/mo), automation middleware like Zapier or Make ($20 to $149/mo), a white-label dashboard (either a wrapper tool like Vapify at $99 to $299/mo, or custom development), Stripe Connect for per-client billing, and a developer to build and maintain the glue layer. Conservative developer cost for the initial build is $8,000 to $15,000. Ongoing maintenance adds $1,500 to $3,000 per month. For an agency at 10 clients, total monthly spend on the DIY Retell stack is typically $1,500 to $2,400 in SaaS fees alone, before the developer. Hermes Agency is $699 per month all-in with no developer required. The comparison is not close once you count everything.
Is Retell faster or more reliable than Hermes?
Retell at the infrastructure layer can achieve p50 latencies of 500ms to 800ms for standard conversational flows. Hermes adds an orchestration layer and targets 600ms to 950ms p50 latency in standard configurations. For most agency use cases, the difference is not perceptible in a live conversation. Reliability is a more important comparison for production agency workloads. Retell has had multiple publicly reported outage events in 2025 and 2026, some impacting production agency deployments for hours. This is a known risk of building on a single-provider infrastructure stack. Hermes builds in provider-level redundancy at the infrastructure layer, so the agency's clients are not directly exposed to single-provider outages. For an agency with 10 clients, an hour of downtime on a Friday afternoon is a support and reputation crisis. Infrastructure reliability matters more than marginal latency differences.
Who should use Retell versus Hermes?
Use Retell if you are a developer building a custom voice AI application where you need API-level control, are not running an agency model, and have engineering resources to build the operations layer yourself. Retell is excellent for product engineers building voice AI into existing software. Use Hermes if you are running an AI voice agency: serving 3 to 20 clients, deploying on their behalf, and needing a complete platform to manage those clients without building infrastructure. If you started on Retell and are spending more developer time on infrastructure maintenance than you are on client delivery, that is the primary signal to move to Hermes. The pivot point for most operators is the third or fourth client, when the DIY stack starts requiring more ongoing maintenance than it is worth.
Outgrown Retell? Hermes is the upgrade.
If you started on Retell and you are spending more time managing infrastructure than serving clients, that is the signal. One platform. Your brand. From $149 per month.
Apply to the Founders' Beta