Vapi vs Retell AI: Which Voice Agent Platform Should You Choose?
A modular, bring-your-own-everything developer platform versus a managed voice stack with all-in pricing and compliance on every plan.
Vapi vs Retell AI is a choice between control and convenience. Vapi is a modular developer platform where you pick every layer of the voice stack. Retell AI is a managed platform with transparent all-in pricing and a visual agent builder.
Both platforms build AI phone agents that answer calls, book appointments, and call functions in real time. Both sit on top of the same core pieces: speech-to-text, a language model, and text-to-speech.
The difference is how much of that stack you want to own. This guide compares real pricing, latency, model flexibility, compliance, and developer experience, so you can pick by use case.
Vapi vs. Retell AI: Side-by-Side
| Dimension | Vapi | Retell AI |
|---|---|---|
| What it is | Modular developer platform for voice agents | Managed voice agent platform with visual builder |
| Price | $0.05/min platform fee + provider costs at cost | $0.07-$0.31/min all-in, components published |
| Latency | Roughly 500-700ms with a tuned stack | Around 600ms out of the box |
| LLM flexibility | Any provider, custom and self-hosted endpoints | Curated list: OpenAI, Anthropic, Google models |
| Concurrency | 10 lines included, $10/line/month extra | 20 concurrent calls free, $8/concurrency/month extra |
| Compliance | SOC 2, HIPAA, PCI on enterprise; HIPAA add-on $2,000/mo | SOC 2 Type II, HIPAA, GDPR included on every plan |
| Telephony | Twilio, Vonage, Telnyx, BYO SIP trunk | Twilio, Vonage, SIP trunking, keep existing numbers |
| Best for | Engineering teams that want full stack control | Teams that want fast launch and predictable costs |
| Bottom line | Pick it for flexibility and custom stacks | Pick it for simplicity and built-in compliance |
What is the difference between Vapi and Retell AI?
The core difference is modularity versus management. Vapi is an orchestration layer that lets you plug in any speech-to-text, language model, and voice you want. Retell AI runs a managed stack with curated choices and publishes one all-in price for the result.
Vapi treats every layer as swappable. You can bring your own API keys for OpenAI, Anthropic, Deepgram, or ElevenLabs, and even point it at a self-hosted model endpoint.
Retell AI trades some of that freedom for speed. Its drag-and-drop agent builder, built-in guardrails, and batch calling get a working agent live fast, without wiring providers together yourself.
- Vapi: modular orchestration, bring your own models, keys, and telephony.
- Retell AI: managed stack, visual builder, all-in per-minute pricing.
Deciding between Vapi and Retell AI for your call handling? We can prototype your call flow on both platforms and tell you which one wins on cost and quality for your volume.
Book a ConsultationVapi vs Retell AI pricing: the per-minute math
Retell AI is easier to predict; Vapi can be cheaper if you optimize. Vapi charges a $0.05 per minute platform fee, then passes through speech-to-text, LLM, and voice costs at cost. Those provider costs drop to $0 on your Vapi bill if you bring your own API keys, because you pay the providers directly.
Retell AI prices the whole stack per minute. The voice engine runs $0.055 per minute, platform voices add $0.015 per minute, and the LLM is priced per model. GPT-4.1 costs $0.045 per minute, Claude 4.6 Sonnet costs $0.08 per minute, and a budget GPT-5 nano agent runs just $0.003 per minute.
Work the math on a common setup. A Retell AI agent on GPT-4.1 with a platform voice lands around $0.115 per minute before telephony ($0.055 + $0.015 + $0.045). A similar Vapi agent starts at $0.05 platform, plus whatever your chosen providers charge, so cheap providers pull the total under Retell and premium voices push it over.
Concurrency and free credits differ too. Retell AI includes $10 in free credits and 20 free concurrent calls, with extra concurrency at $8 per line per month. Vapi includes 10 concurrent lines and charges $10 per extra line per month.
Features and flexibility: BYO everything vs curated stack
Vapi wins on flexibility; Retell AI wins on packaged features. Vapi supports any LLM provider, including self-hosted endpoints, and lets you mix voices from ElevenLabs, Cartesia, and other TTS vendors. That makes it the stronger base for unusual stacks and heavy customization.
Retell AI supports a curated model list from OpenAI, Anthropic, and Google, but not self-hosted models. In exchange, it ships batch call campaigns, automatic PII redaction, knowledge bases, and an AI quality-assurance layer as platform features.
On telephony, both connect to Twilio and Vonage and support SIP trunking, so you can keep existing numbers. Retell AI makes carrier setup simpler out of the box, while Vapi gives you more room to wire in custom SIP infrastructure.
Latency is close between them. Third-party tests in 2026 put a tuned Vapi stack around 500 to 700 milliseconds, while Retell AI averages about 600 milliseconds with no tuning.
Compliance and enterprise readiness
Retell AI includes more compliance by default. It states it is fully compliant with HIPAA, SOC 2 Type II, and GDPR, and those protections apply across plans rather than sitting behind an enterprise tier.
Vapi gates its strongest guarantees behind paid add-ons or enterprise. HIPAA mode requires a signed BAA plus an Enterprise subscription or a $2,000 per month HIPAA add-on, and Zero Data Retention is a separate $1,000 per month add-on. Its Scale plan lists SOC 2, HIPAA, PCI, SSO, and RBAC.
For healthcare, insurance, and finance teams, that gap matters at small scale. A clinic doing modest call volume gets HIPAA on Retell AI without a four-figure monthly add-on, while a large enterprise negotiating a Vapi Scale contract gets the same certifications bundled.
Developer experience: API depth vs speed to launch
Vapi is built API-first for engineers; Retell AI is built for fast launches by mixed teams. Vapi exposes thousands of configuration points, SDKs for web and mobile, and workflow tooling, which rewards teams that want to tune every stage of a call.
Retell AI pairs its API with a drag-and-drop agent builder, so non-technical teammates can edit prompts and call flows. Many teams get a test agent live the same day they sign up.
Neither platform locks developers out. Both offer solid APIs, webhooks, and real-time function calling for booking, payments, and transfers. The honest read: Vapi has the deeper control surface, and Retell AI has the shorter path from idea to a live phone number.
Which should you choose?
Choose Vapi if you have engineers and strong opinions about your stack. It fits teams that want to swap models freely, self-host an LLM, tune latency per layer, or build voice into a product with full API control.
Choose Retell AI if you want predictable all-in pricing, built-in compliance, and a fast launch. It fits agencies, clinics, and operations teams that need a reliable phone agent more than a custom voice pipeline.
If you are still unsure, prototype on both. Retell AI includes $10 in free credits, and both platforms let you test a live call in under an hour.
- Choose Vapi for BYO models, custom stacks, and deep API control.
- Choose Retell AI for all-in pricing, bundled compliance, and speed to launch.
The Verdict
Vapi vs Retell AI comes down to how much of the voice stack you want to own. Vapi is the better pick for engineering teams that want modular control: any LLM including self-hosted, swappable voices, custom SIP, and a $0.05 per minute platform fee with provider costs passed through at cost.
Retell AI is the better pick for teams that want a managed platform. Its $0.07 to $0.31 per minute all-in pricing is easy to forecast, SOC 2 Type II, HIPAA, and GDPR come standard, and the visual builder gets agents live fast without deep engineering time.
For regulated industries at small scale, Retell AI usually wins on total cost because compliance is bundled. For high-volume products with a tuned cheap stack, Vapi usually wins on unit economics. Run a short pilot on your real call flow before committing.
Researched from primary vendor documentation and public regulator sources. Pricing and availability are accurate as of Jul 16, 2026 and can change — confirm current terms with each vendor before you buy.
Frequently Asked Questions
- Vapi is better for engineering teams that want full control: any LLM including self-hosted models, swappable voices, and deep API configuration. Retell AI is better for teams that want all-in pricing, bundled SOC 2 Type II and HIPAA compliance, and a visual builder for fast launches. The right pick depends on your team and use case.
- It depends on your stack. Vapi charges $0.05 per minute plus provider costs at cost, so a cheap speech and model stack can undercut Retell AI. Retell AI runs $0.07 to $0.31 per minute all-in, and a typical GPT-4.1 agent lands around $0.115 per minute before telephony, which is easier to predict.
- Yes. Retell AI states it is fully compliant with HIPAA, SOC 2 Type II, and GDPR, and it offers features like automatic PII redaction. That compliance comes standard rather than as a paid add-on, which matters for smaller healthcare teams.
- Yes. Vapi supports any LLM provider, including OpenAI, Anthropic, and Google models, plus custom and self-hosted endpoints. You can also bring your own API keys, so model costs are billed by your provider directly instead of through Vapi.
- Yes, outside of enterprise plans. Vapi requires a signed BAA plus either an Enterprise subscription or a HIPAA add-on listed at $2,000 per month. A separate Zero Data Retention add-on is listed at $1,000 per month, and the two modes cannot run together.
- They are close. Third-party tests in 2026 put Retell AI around 600 milliseconds out of the box, while a well-tuned Vapi stack measures roughly 500 to 700 milliseconds. Vapi can edge lower with tuning; Retell AI is faster to get low latency without any tuning.
Not sure which voice agent platform fits your call volume?
We help teams pick, build, and deploy AI voice agents on the right platform for their stack and budget. Book a consultation and we will map Vapi or Retell AI to your actual call flows.
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