AgentStack REI

Retell AI

Pay-as-you-go voice AI platform for building inbound and outbound phone agents, with no platform fee on the self-serve plan.

Price

Pay-as-you-go from $0.07-$0.31/minute; no monthly platform fee

Default cost-estimator example on the pricing page was $0.11/min (LLM $0.04, Retell Voice Infra $0.055, TTS $0.015, telephony $0.00 in that example). US Twilio telephony is listed at $0.015/min. 20 concurrent calls included, then $8/concurrency/month. Batch Call +$0.005/dial. Retell phone numbers $2/month. SMS $0.01/message. Enterprise is custom.

Free trial: Vendor says Retell starts at $0 and you pay only for what you use; you can sign up for the pay-as-you-go plan for free. Not a dated trial.

Price checked Nov 13, 2026 · source

Visit retellai.com →

What it can do

  • Build and test voice agents with templates, simulation testing, transcripts, and analytics
  • Place and receive calls; transfer to a human (AI voice fee stops after transfer; telephony may continue)
  • Batch outbound calling, SMS, knowledge bases, and webhooks/API
  • Choose LLM and voice providers; SOC 2 and HIPAA-ready options on enterprise terms

What it can't do / limits

  • You assemble the agent yourself; it is a platform, not a prebuilt wholesaling dialer
  • 20 concurrent calls free, then $8 each per month; Enterprise for uncapped concurrency
  • You are billed for connected call duration, including silence/hold, because STT stays active; failed connects are not billed
  • AI-generated voices are treated as artificial voices under the TCPA, so cold outbound to residential lists generally requires prior express consent; this is a legal constraint on use, not a vendor feature claim

Who it fits

Investors or operators who can build or hire someone to build a custom voice agent, especially for inbound and opted-in follow-up calling.

Spot an outdated price or a wrong fact? Tell us.

Price changes, every Tuesday

Get new tools and price changes in one short email.

Free. Every Tuesday: one real investor stack, new tools, price changes. Unsubscribe anytime.

Other cold calling tools

Bland AI

Start plan $0 platform fee at $0.14/min

Voice AI platform with an all-in per-minute rate that includes LLM, STT, and TTS; telephony billed separately.

Leadialer

No monthly platform fee

Pay-as-you-go AI dialer marketed to wholesalers, with cascade dialing, SMS follow-up, and an all-in $0.10/min voice rate.

Synthflow

Pricing not public

Enterprise conversational AI platform for voice agents, sold as an annual contract rather than self-serve per-minute billing.