Retell AI alternatives

Retell AI is a voice AI platform. Its pages describe it this way: A pay-as-you-go voice agent platform with a visual flow builder and API, bundling voice infrastructure in the per-minute rate while LLM, voice and telephony are priced as selectable line items. Reviewed October 10, 2026.

Last verified October 10, 2026.

We make Calldesk, so it appears below as one of the options, and we say so. Options are listed alphabetically, not ranked.

Who Retell AI suits

We file Retell AI under voice AI platforms, where you build and run agents yourself, and it bills by usage. The audience its pages name is teams that want a self-serve, usage-priced voice agent platform with a visual builder and a wide choice of models and voices, from startups through regulated enterprises.

What Retell AI does well

Strengths Retell AI's own pages describe, each linked to its source:

  • True pay-as-you-go with no contract and 20 concurrent calls included, so small teams can start without a sales call. (source: retellai.com)
  • Wide choice of LLMs (OpenAI, Anthropic, Google, custom LLM over WebSocket) and voice providers with transparent per-minute rates listed publicly. (source: retellai.com)
  • Self-service BAA and DPA signing at no extra fee, with per-agent data retention and PII controls documented. (source: docs.retellai.com)
  • Broad telephony options: Retell-purchased numbers or custom telephony via elastic SIP trunking, with guides for Twilio, Telnyx, Vonage, Genesys, Five9 and Avaya. (source: docs.retellai.com)
  • Built-in tooling beyond calls: simulation testing, AI quality assurance, batch calling, call transfer, SMS and verified/branded caller ID. (source: retellai.com)

How Retell AI prices

On a platform that bills by usage, check what the headline rate covers. Retell AI describes its model as: Pay as you go, no subscription: a voice infrastructure rate plus the chosen LLM, voice and telephony per minute, with optional add-ons; custom enterprise pricing.

What the published figure says: $0.07 to $0.31 per minute depending on the model and voice chosen; voice infrastructure is $0.055 per minute, and the vendor's example configuration totals $0.11 per minute.

  • Pay-as-you-go includes full platform access and 20 concurrent calls free; additional concurrency is $8 per concurrent call per month. (source: retellai.com)
  • Enterprise: custom pricing, custom MSA/DPA, SSO, role-based access control, no cap on concurrent calls. (source: retellai.com)
  • Example from the page: Retell platform voice $0.015, LLM about $0.04 (varies by model), voice infrastructure $0.055 = $0.11 per minute. (source: retellai.com)
  • Phone numbers: $2 per month for US and Canada numbers purchased from Retell; US toll-free $5 per month (docs). (source: retellai.com)
  • Testing is billed at production rates (docs). (source: retellai.com)

Billed separately or extra on Retell AI, which matters when you total a month:

  • LLM: per-minute, depends on model (examples: GPT 4.1 mini $0.0128, GPT 5 $0.04, Claude Sonnet $0.064 to $0.08) (source: retellai.com)
  • Text-to-speech: $0.015 per minute for Retell platform voices; ElevenLabs voices $0.04 to $0.10 per minute (source: retellai.com)
  • Telephony: about $0.015 per minute on Retell Twilio/Telnyx numbers; no charge for custom telephony/SIP trunking (source: retellai.com)
  • Optional add-ons: Knowledge Base +$0.005/min, Advanced Denoising +$0.005/min, Safety Guardrails +$0.005/min, PII Removal +$0.01/min, Batch Call +$0.005/dial, Branded Call +$0.10 per outbound call (source: retellai.com)
  • Phone number $2/month, verified phone number $10/month, SMS $0.01 per message (source: retellai.com)

Trying it first: $10 in free credits on sign-up.

Limits to know about Retell AI

Described on Retell AI's own pages; whether they matter depends on your calls.

  • Retell-purchased phone numbers are limited to the US and Canada, and outbound calls from them are supported to 15 countries; other countries need custom telephony. (source: docs.retellai.com)
  • Per-minute cost varies widely ($0.07 to $0.31) with model and voice, and several features (knowledge base, denoising, guardrails, PII removal) are priced as per-minute add-ons. (source: retellai.com)
  • The vendor states it does not currently operate services within the European Union. (source: docs.retellai.com)

Integrations and telephony at Retell AI

Retell AI's pages name these connections: Twilio, Telnyx, Vonage, Genesys Cloud, Five9, Avaya, Make, n8n, HubSpot, Go High Level, Google Drive, OneDrive and Notion knowledge-base sync and Custom LLM over WebSocket. Test the one you depend on.

  • Bring your own carrier: Retell AI's pages say this is supported. (source: docs.retellai.com)
  • Numbers from the provider: Retell sells US and Canada numbers ($2 per month; US toll-free $5 per month); custom telephony via SIP trunking or SIP URI is supported with no Retell charge for the trunk. (source: docs.retellai.com)

Compliance as stated by Retell AI

Retell AI's pages mention HIPAA, SOC 2 and GDPR. These are the vendor's own statements and we have not audited them.

  • Wording on file for Retell AI, from the page titled "Retell docs: Security and compliance": Stated by vendor, self-attested: documentation says HIPAA compliant (BAA required), SOC 2 Type 1 and Type 2 certified, and GDPR compliant via AWS with a DPA. A Vanta trust center is referenced but was not opened. (source: docs.retellai.com)

What to check before choosing an alternative to Retell AI

Retell AI's pages describe 3 conditions and leave 4 points open; these questions start there. Put each one to every option you shortlist.

  1. Number setup: Retell sells US and Canada numbers ($2 per month; US toll-free $5 per month); custom telephony via SIP trunking or SIP URI is supported with no Retell charge for the trunk. Check whether a new number, a forwarded line or your own carrier is the normal route with each option. (source: docs.retellai.com)
  2. Hands-on test: Retell AI states: $10 in free credits on sign-up. Ask each option for a test of the same depth, with your own script. (source: retellai.com)
  3. Your tools: Retell AI names Twilio, Telnyx and Vonage among its integrations. Check your own list of systems against each option, not a count.
  4. Concurrency: ask each option, Retell AI included, how many calls can run at once on the plan you would choose and what raising that costs.
  5. What the rate covers: ask what Retell AI's per-minute figure includes and what it leaves out, and ask the same of each option's own figure, before comparing numbers. (source: retellai.com)
  6. Leaving Retell AI: the first step its pages give is to retrieve agent settings with the List/Get Voice Agent API and the prompt/states with the Get Retell LLM or conversation flow endpoints. Ask each option what moving in would involve. (source: docs.retellai.com)
  7. Keeping your numbers: Retell AI supports bringing your own carrier, so check that every option on your list accepts the carrier you have. (source: docs.retellai.com)
  8. Whole bill: Retell AI's pages list LLM, text-to-speech and telephony as billed separately or extra, so price a full month with every charge in it. (source: retellai.com)
  9. A condition on Retell AI's pages: Retell-purchased phone numbers are limited to the US and Canada, and outbound calls from them are supported to 15 countries; other countries need custom telephony. Decide whether it applies to your calls. (source: docs.retellai.com)

Where Calldesk fits and where it may not

We make Calldesk, so this section includes the cases where Retell AI is the better match.

Where Calldesk may fit better:

  • Its pricing model, in Retell AI's words: Pay as you go, no subscription: a voice infrastructure rate plus the chosen LLM, voice and telephony per minute, with optional add-ons. Calldesk bills one per-minute rate per plan (2¢ to 9¢ per minute depending on the plan, with no monthly minimum, plus phone carrier charges), which may be easier to total without separate lines for the parts of a call.
  • Calldesk has a REST API, an MCP server and signed webhooks (/docs) if you want to drive agents from code, but it is a packaged agent, not a set of parts to assemble.

Where Retell AI may fit better:

  • Wide choice of LLMs (OpenAI, Anthropic, Google, custom LLM over WebSocket) and voice providers with transparent per-minute rates listed publicly. Check whether Calldesk offers the same before you leave Retell AI. (source: retellai.com)
  • Broad telephony options: Retell-purchased numbers or custom telephony via elastic SIP trunking, with guides for Twilio, Telnyx, Vonage, Genesys, Five9 and Avaya. Compare this with the Calldesk pricing page and docs before you decide. (source: docs.retellai.com)
  • Retell AI's pages mention HIPAA, SOC 2 and GDPR, while Calldesk claims no certification. If that wording matters to your buyers, Retell AI may be the safer starting point. (source: docs.retellai.com)
  • Retell AI's pages describe SIP trunking, and Calldesk does not offer it. If you connect your phone system by SIP trunk, Retell AI may be the better match. (source: docs.retellai.com)

Other options to consider besides Retell AI

  • Bolna

    Bolna is also a voice AI platform, and it bills by usage as Retell AI does. Both list Twilio and n8n among their integrations. Bolna's pages did not mention HIPAA, SOC 2 or GDPR where we looked, while Retell AI's pages mention HIPAA, SOC 2 and GDPR.

    Verified 2026-10-10 (source: bolna.ai)

  • Calldesk

    Per-minute plans (Lite 2¢, Standard 5¢ and Pro 9¢ per minute), with phone carrier charges billed separately. You can register a number you own and forward calls to it; SIP trunking is not offered. Our own product.

    Made by the publisher of this page

  • ThunderPhone

    ThunderPhone is also a voice AI platform, and it bills by usage as Retell AI does. Both list Twilio and Telnyx among their integrations. ThunderPhone's pages mention HIPAA and GDPR, while Retell AI's pages mention HIPAA, SOC 2 and GDPR.

    Verified 2026-10-10 (source: thunderphone.com)

  • Vapi

    Vapi is also a voice AI platform, and it bills by usage as Retell AI does. Both list Twilio and Telnyx among their integrations. The pages of both mention HIPAA, SOC 2 and GDPR.

    Verified 2026-10-10 (source: vapi.ai)

What we could not confirm about Retell AI

  • Exact HIPAA/BAA availability by plan is shown in a comparison table whose cell values we could not read; the compliance documentation says BAA/DPA self-signing has no additional fee.
  • Whether Retell-provided numbers can be ported out was not found.
  • The Vanta trust center was not opened.
  • The pricing page lists future-dated model names; per-model rates should be re-checked on the live page before quoting a specific model price.

What we read about Retell AI

This page rests on 9 pages from Retell AI's public site, last read on October 10, 2026. The facts above came from "Retell AI pricing page" (pricing, strengths and limits), "Retell docs: Testing pricing" (pricing), "Retell docs: Purchase phone number" (pricing and limits), "Retell docs: Security and compliance" (compliance wording, strengths and limits) and "Retell docs: Custom telephony" (phone setup and strengths). Anything those pages did not say is shown as not stated, not guessed.

Details about Retell AI come from its public pages as they were on October 10, 2026. Retell AI may have changed them since, and a page that was unclear to us may be clear to you. Corrections: support@calldesk.tech. We make Calldesk, so read this page with that in mind and check anything important with Retell AI directly.

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