Looking for a Retell AI alternative?
Sempera and Retell AI both build voice AI platforms. Sempera is built on proprietary infrastructure for regulated industries. Retell assembles third-party APIs for developers and agencies.
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Sempera and Retell AI are both voice AI platforms, but they serve different markets. Sempera is an enterprise voice AI platform built on proprietary infrastructure for regulated industries (insurance, healthcare, financial services, debt collection) with SOC 2 Type II, HIPAA, and PCI DSS compliance. Retell AI is a developer-focused platform built on third-party APIs for mid-market and agency use cases.
What teams run into with Retell AI
Data crosses third-party providers
Retell stitches OpenAI, ElevenLabs, and Twilio together. Every call exposes customer data to three external providers, each with its own retention and compliance posture.
Provider bills stack on top of the platform fee
Retell's per-minute price covers orchestration. You still get separate invoices for the underlying LLM, TTS, and telephony providers. Total cost compounds at scale.
Compliance gets verified, not certified
SOC 2, HIPAA, and PCI DSS posture depends on which providers you wire in. Enterprise security reviews ask for documentation Retell can't produce on its own.
Why teams switch to Sempera
Licensed platform
Sempera licenses its voice platform rather than building the models itself. Call data is handled by that platform and by a telephony carrier, both named in the sub-processor list.
Enterprise compliance
SOC 2 Type II, HIPAA with BAAs, PCI DSS, GDPR. Sempera has passed security reviews at a top-10 US bank.
On-premise deployment
Sempera offers full on-premise and VPC deployment for enterprises that require zero data egress. Retell offers on-premise on its enterprise tier.
Field deployment engineering
Sempera's FDE team flies on-site for large deployments. Dedicated engineers for major accounts. Not ticket-based support.
Predictable pricing
$0.11 to $0.14/min covers transcription, inference, and TTS, with no separate charges for third-party providers.
Sempera vs Retell AI, line by line
| Feature | Sempera | Retell AI |
|---|---|---|
| Infrastructure | Licensed models (transcription, LLM, TTS) | Third-party APIs (OpenAI, ElevenLabs, Twilio) |
| Data sovereignty | Calls never sent to a frontier model provider | Data processed by multiple third-party providers |
| End-to-end latency | Under 400ms | Varies by provider chain |
| SOC 2 Type II | Yes | Verify with Retell |
| HIPAA compliance | Yes, with BAA | Verify with Retell |
| PCI DSS | Yes | Verify with Retell |
| On-premise deployment | Yes (Cloud, VPC, On-Premise) | Cloud; on-premise on enterprise |
| Languages | 40+ | Multiple (verify current count) |
| Agent builder | Norm (natural language) + Pathways (visual flow) | Dashboard + templates |
| Enterprise support | Dedicated FDE team, on-site support, SLA | Email, community |
| Pricing model | $0.11 to $0.14/min all-inclusive | Per-minute + component fees |
| Call volume | 100M+ calls/month in production | Not disclosed |
| Target market | Enterprise (100+ agent contact centers) | Mid-market, agencies, developers |
See the full breakdown: Sempera vs Retell AI.
Retell AI alternative FAQ
Sempera and Retell serve different markets. Sempera is built for enterprise contact centers in regulated industries needing SOC 2, HIPAA, PCI DSS, data sovereignty, and on-premise deployment. Retell is built for developers and agencies needing quick setup with third-party AI providers. Choose based on your compliance, data privacy, and scale requirements.
No. Sempera runs entirely on proprietary AI models. Customer data never passes through OpenAI, Anthropic, Google, or any third-party AI provider. Retell AI uses third-party providers for LLM inference and voice synthesis. This is the core architectural difference between the two platforms.
Sempera charges $0.11 to $0.14 per minute all-inclusive covering the full voice AI stack. Retell charges per minute plus separate fees for telephony and third-party AI providers. At enterprise scale, Sempera's all-inclusive pricing is often more cost-effective and predictable.
Yes. Sempera's implementation team has experience migrating enterprise customers from other voice AI platforms. The typical migration includes agent reconfiguration, integration reconnection, and a parallel-run testing period. Contact Sempera's sales team to discuss migration.
