Last verified October 10, 2026.
Details about ThunderPhone come from its public pages as they were on October 10, 2026. ThunderPhone 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 ThunderPhone directly.
About ThunderPhone
How ThunderPhone positions itself: A voice agent platform that runs its own speech-to-speech stack and sells flat, all-inclusive per-minute tiers, with importers for agents built on other platforms.
Side by side
A row is shown when we could read both sides. Where ThunderPhone's pages did not say, a cell reads "not stated on the pages we reviewed" rather than a guess. It rests on published pricing, setup and wording, and does not use call-quality or benchmark results.
| Topic | Calldesk | ThunderPhone |
|---|---|---|
| How pricing works | Per minute of call time on three plans: Lite 2¢, Standard 5¢, Pro 9¢. No monthly minimum. Phone carrier charges are billed separately. | Prepaid pay-as-you-go with three flat per-minute engine tiers (Spark, Bolt, Storm) and optional per-minute add-ons; no subscription or seat fee. (source: thunderphone.com) |
| Published starting price | 2¢ to 9¢ per minute depending on the plan, before phone carrier charges | From 2 cents per minute (Spark), 5 cents (Bolt) and 9 cents (Storm), all-inclusive of transcription, model and standard voices; add-ons such as premium voices apply extra. (source: thunderphone.com) |
| Billed separately or extra | The phone carrier is billed separately unless you buy numbers from us; Expert backup is an optional extra on Lite and Standard at 1.5 cents per minute | Premium voices and selected languages (up to +3 cents per minute); Long prompts, supervision and Storm options (see plan notes); ThunderPhone-provided phone numbers ($1 per month plus 1 cent per minute for inbound); Outbound telephony on your own carrier (source: thunderphone.com) |
| Trying it first | A free demo call on the Calldesk site | $10 of free call credit on every new account, no credit card required. (source: thunderphone.com) |
| Bring your own carrier | Yes, on every plan, at no extra charge, by forwarding calls to a number you register (no SIP trunking) | Yes (source: thunderphone.com) |
| Phone numbers from the provider | A paid extra on every plan: Telnyx $1.00 per month per number plus 1 cent per inbound minute; Twilio $2.00 per month per number plus 1.5 cents per inbound minute. Registering a number you already own costs nothing extra. | US numbers from ThunderPhone at $1 per month per number plus 1 cent per minute inbound; own numbers via Twilio, Telnyx (by API key) or SignalWire, Vonage, Plivo and any SIP trunk. (source: thunderphone.com) |
| HIPAA | Not claimed | Stated on their pages (source: thunderphone.com) |
| SOC 2 | Not claimed | Not stated on the pages we reviewed (source: thunderphone.com) |
| GDPR | Not claimed | Stated on their pages (source: thunderphone.com) |
| Integrations and developer tools | REST API, MCP server and signed webhooks, plus calendar booking | Twilio, Telnyx, SignalWire, Vonage, Plivo, SIP trunks, Google, Slack and HubSpot app connections, Zapier, n8n, MCP servers, LiveKit Agents, Pipecat and OpenAI Realtime clients |
About ThunderPhone's compliance wording: Stated by vendor, self-attested: the trust center lists HIPAA, GDPR and UK GDPR as compliant with 107 controls monitored; BAA and DPA at no extra charge. SOC 2 is not named on the pages read.
ThunderPhone pricing details
- Prepaid and pay-as-you-go; no platform fee, subscription or seat fee. (source: thunderphone.com)
- Hold time bills at a flat 2 cents per minute on every tier. (source: thunderphone.com)
- Optional add-ons: Storm extra intelligence +3 cents, Storm verbal acknowledgement +2 cents, supervision +4 cents, selected-language or premium voice up to +3 cents, long prompts beyond 5,000 tokens +1 to +2 cents per block, ThunderPhone number usage +1 cent per minute. (source: thunderphone.com)
- Enterprise: custom rates, the vendor says 1 cent per minute or less is possible for some high-volume outbound use cases. (source: thunderphone.com)
- ThunderPhone numbers: US numbers at $1 per month per number (pricing page). (source: thunderphone.com)
What ThunderPhone does well
- Flat per-minute pricing that includes transcription, the model and standard voices, with no platform fee and a lower flat rate while on hold. (source: thunderphone.com)
- Agent importers for Vapi, Retell, ElevenLabs Agents and Bland via API key or JSON export, with a review step before anything is created. (source: thunderphone.com)
- Built-in operations tooling: A/B experiments, AI-graded test calls, live call supervision, validation sets, campaigns with timezone windows and retries, and client portals. (source: thunderphone.com)
- States HIPAA, GDPR and UK GDPR compliance with a BAA and DPA at no extra charge and a public trust center. (source: thunderphone.com)
- Carrier flexibility: native SIP trunking, bring-your-own numbers via Twilio, Telnyx, SignalWire, Vonage, Plivo, and 40+ languages understood. (source: thunderphone.com)
Conditions to check with ThunderPhone
These are limits or conditions described on the pages we reviewed. We list them so you can check whether they matter for your calls.
- The all-in base rates exclude premium voices, selected languages, long prompts and ThunderPhone numbers, which are separate per-minute add-ons. (source: thunderphone.com)
- ThunderPhone lists cold outbound calling as a separate human-agent service (ThunderHuman) rather than as part of the AI platform alone. (source: thunderphone.com)
- ThunderPhone numbers are US numbers on the pricing page; the vendor says to bring your own carrier for outbound. (source: thunderphone.com)
Where Calldesk is different
- Billing: ThunderPhone's headline price does not cover premium voices and selected languages, long prompts, supervision and Storm options, ThunderPhone-provided phone numbers and outbound telephony on your own carrier, which its pages bill separately or as extras (the table above has the details). Calldesk bills one per-minute rate for the plan you choose (Lite 2¢, Standard 5¢ and Pro 9¢ per minute), and the phone carrier is billed separately unless you buy numbers from us. Compare the two on a month of your own calls.
- Phone setup: both support bringing your own carrier. With Calldesk you register a number you own and forward calls to it. Calldesk does not offer SIP trunking, which ThunderPhone's pages describe. Calldesk also sells numbers from Telnyx and Twilio if you prefer not to bring one.
- Languages: Calldesk supports 40+ languages, including English; agents in a language other than English need the Standard or Pro voice, because the Lite voice speaks English only.
- Developer tools: Calldesk has a REST API, an MCP server and signed webhooks for call.completed, call.transferred and call.analyzed events (/docs).
- Compliance: Calldesk does not currently claim any compliance certification, so if your industry requires one, ask us what we can show you before you rely on it.
Which one fits
ThunderPhone may suit you if this describes you: cost-sensitive teams that want a flat per-minute price and a way to import existing agents from other platforms.
Calldesk may suit you if your calls match one of its plans. Lite is for straightforward calls such as confirmations and quick questions, where cost matters most. Standard is for most businesses: reception, booking, intake and after-hours coverage. Pro is for complex or high-stakes calls where reasoning and tone matter most. Current prices are on the pricing page at /pricing.
What we could not confirm about ThunderPhone
- How to export agents out of ThunderPhone was not documented on the pages read.
- SOC 2 status not stated.
- We did not research ThunderPhone's company history, customer base or independent reliability data.
- We did not verify benchmark results or price comparisons that ThunderPhone publishes on its own pages.
- Country coverage for ThunderPhone-provided numbers beyond the US was not found.
Sources
- ThunderPhone pricing page (retrieved October 10, 2026)
- ThunderPhone docs: pricing and usage charges (retrieved October 10, 2026)
- ThunderPhone homepage (retrieved October 10, 2026)
- ThunderPhone agent import (retrieved October 10, 2026)
- ThunderPhone trust center (retrieved October 10, 2026)
- ThunderPhone enterprise page (retrieved October 10, 2026)
- ThunderPhone docs index (retrieved October 10, 2026)
- ThunderPhone docs: Import agents (retrieved October 10, 2026)