How Much Does a Voice AI Agent Cost Per Minute? (2026)

Components of Voice AI Costs

A voice agent on the phone typically incurs five distinct bills, which can be calculated as a cost per minute of the call:

• Phone Line: A US number costs approximately $1 per month, with calls ranging from 0.5 to 1.5 cents per minute. Some carriers round call duration up to the nearest minute.
• Speech-to-Text: This is billed per minute of audio (typically 0.2 to 2 cents), covering the entire duration of the call, including silence.
• Language Model: Billed per token. Because the model reads the entire conversation history on every turn, input tokens accumulate quickly. Prompt caching can reduce this cost by three to five times, provided the prompt meets a minimum length requirement (500 to 4,000 tokens). With caching, a small model costs under 1 cent per minute, whereas larger models or uncached setups can cost 2 cents or more.
• Text-to-Speech (Voice): Billed per character spoken by the agent. Since the agent speaks for roughly half the call, this adds 0.2 to 3 cents per minute. Charges apply to all generated text, even if the caller interrupts the agent.
• Platform: The service that coordinates the components and manages turn-taking. Platform fees range from 1 to 5.5 cents per minute. Some platforms pass through other layer costs at cost, while others offer bundled pricing (7 to over 15 cents per minute). Alternatively, developers can self-host open-source frameworks and pay for server costs directly.

Speech-to-Speech Models

Speech-to-speech models consolidate speech-to-text, the language model, and text-to-speech into a single service. They charge for audio input and output, often by the token, and resend the conversation history on each turn. This single model can cost between 2.5 and 8 cents per minute, and up to 30 cents per minute if caching fails. Phone line and platform fees still apply on top of this cost.

Hidden Costs and Real-World Pricing

Beyond the standard per-minute rates, several hidden factors affect the final bill:

• Recordings and monthly storage fees.
• Call transfers, which require paying for a second phone line plus the human agent's time.
• Test calls, which are billed at standard rates.
• Short calls, such as hang-ups and voicemails, which may be rounded up to a full minute by carriers.

To determine the true cost of a voice AI system, organizations should calculate the cost per successful call rather than just the cost per minute. For example, if a five-minute call costs 43 cents and has a 78% success rate, the actual cost per successful call is approximately 60 cents.