AI Voice Agent Vendors

Millis AI

Voice agent platforms

Millis AI, from TMate Inc., is a developer platform for building low-latency voice agents for phone calls, websites and apps. Builders create agents in a web playground or through its API and SDKs, choose LLM and voice providers or connect their own LLM, and link phone numbers from carriers such as Twilio, Vonage, Plivo and Exotel. It charges a per-minute platform fee, with model and speech costs billed on top.

Visit Millis AIPricing page

Charges by
Usage-based
Starts at
$0.02/min
Per minute
$0.02
How it works
AI only
Checked
October 15, 2026

Pricing

Millis charges 'a base rate of $0.02 per minute for using the Millis AI platform'. LLM, text-to-speech and speech-to-text are billed on top of that rate. The pricing page doesn't say whether telephony is included or how carrier minutes are billed. Published LLM estimates per minute: GPT-4o $0.004, GPT-4 Turbo $0.008, GPT-3.5 Turbo $0.0004, Meta Llama-3 $0.00018, own LLM no charge. TTS per 1,000 characters (approximate per minute at about 500 characters/min): ElevenLabs $0.10 (~$0.05), OpenAI $0.015 (~$0.0075), Cartesia $0.0392 (~$0.0196), PlayHT $0.25 (~$0.125), Deepgram $0.015 (~$0.0075), Neets $0.001 (~$0.0005), Rime $0.075 (~$0.0375). STT is $0.0043/min. Millis's worked example of a 10-minute session on GPT-4o and ElevenLabs totals $0.6615. ElevenLabs volume discounts of up to 25% are available on request. No monthly plan, free tier, concurrency limit or phone-number price is listed. The homepage says 'starting at just $0.02/min'. The pricing page still names older models (GPT-4 Turbo, GPT-3.5 Turbo) although the changelog added GPT-4.1 in April 2025, so it may not be fully current.

What it does

Answers inbound calls
Yes
Places outbound calls
Yes
Books appointments
Yes
Warm transfer to a person
Unconfirmed
Text follow-up
Unconfirmed
Call recording
Yes
Transcripts
Unconfirmed
CRM sync
Unconfirmed
Keep your number (porting)
Unconfirmed
Spanish
Yes
Other languages
Yes
Web chat
Unconfirmed
API
Yes
Custom voice
Yes

The docs introduction lists 32 supported languages, including Spanish. A February 2025 changelog entry lets an agent focus on a defined list of languages. An April 2025 entry says the Gladia Solaria speech-to-text upgrade supports 100 languages. Actual coverage depends on the voice and speech providers chosen.

Integrations

As listed by Millis AI. Integrations not listed may still be possible through an API or Zapier.

Security and compliance

Signs a HIPAA BAA
Unconfirmed
SOC 2
Unconfirmed
Discloses it's an AI
Unconfirmed

None of the Millis pages reviewed (homepage, docs introduction, pricing, regions, changelog) mention HIPAA or a BAA.

“Unconfirmed” means Millis AI's public pages don't say either way. Rules for AI phone calls

Company

Built for
Small business
Built on
Customer-selected providers: LLMs from OpenAI, open-source models such as Llama and Mistral, or the customer's own LLM; voices from ElevenLabs, OpenAI, Cartesia, Deepgram, Rime, PlayHT, Neets and others in the voice API (including Hume, Sesame, Orpheus, Kokoro and Sarvam); speech recognition including Gladia (per the Millis homepage, pricing docs, voice API reference and changelog).

Sources

  1. Millis AI homepage company, features, pricing. Accessed October 15, 2026
  2. Millis AI pricing overview (docs) pricing. Accessed October 15, 2026
  3. Millis AI docs: introduction company, features. Accessed October 15, 2026
  4. Millis AI docs: inbound call features, integrations. Accessed October 15, 2026
  5. Millis AI docs: outbound call features. Accessed October 15, 2026
  6. Millis AI docs: import phone number integrations, features. Accessed October 15, 2026
  7. Millis AI API: purchase phone number features. Accessed October 15, 2026
  8. Millis AI docs: custom LLM features. Accessed October 15, 2026
  9. Millis AI docs: functions for agents features. Accessed October 15, 2026
  10. Millis AI docs: regions compliance, features. Accessed October 15, 2026
  11. Millis AI tutorial: appointment scheduling agent features, integrations. Accessed October 15, 2026
  12. Millis AI API: get custom voices features. Accessed October 15, 2026
  13. Millis AI documentation index features, integrations. Accessed October 15, 2026
  14. Millis AI changelog features, status. Accessed October 15, 2026
  15. Millis AI affiliate program affiliate. Accessed October 15, 2026
  16. Millis AI terms page company. Accessed October 15, 2026

Spot something out of date? Email contact@aivoiceagentvendors.com with a link to the vendor's page.

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