AI Voice Agent Cost: Per-Minute Pricing Explained

An AI voice agent for a growing business typically costs $0.10 to $0.35 per minute of conversation to run, and $8,000 to $40,000 to build if you have it made for your own phone line, calendar and CRM. A simple agent that answers calls, takes messages and books into one calendar sits at the low end. An agent that looks up orders, takes payments or transfers callers with full context sits at the high end. Off-the-shelf AI receptionist subscriptions run from about $50 to $500 a month, but they only handle the calls they were designed for. This guide breaks a voice agent's cost into its real parts so you can compare a per-minute platform, a subscription and a custom quote on the same basis.

This post is part of our series on AI agent costs and ROI. For what custom agents of every kind cost to build and run, see the main guide at wizeb.com/blog/ai-agent-cost-guide.

Why Voice Agents Cost More Than Chatbots

A chatbot pays for one thing per message: the language model. A voice agent pays for four things every second a caller is on the line, and all four are billed by the minute.

• Telephony. The phone number and the call itself, billed by a carrier such as Twilio or Telnyx. Inbound US calls are usually around a cent a minute, more for toll-free numbers, mobile numbers and international calls.
• Speech-to-text. Turning the caller's words into text in real time, fast enough that the agent can reply without an awkward pause.
• The language model. Deciding what to say and which system to check. This is where most of the price variation comes from, because a larger model costs several times more per minute than a small one.
• Text-to-speech. Turning the reply into a natural voice. Premium voices cost noticeably more than standard ones.

On top of those sits the orchestration layer that keeps them in sync, handles interruptions and passes calls to a person. That is what voice platforms sell. If you are pricing a text chatbot instead, our guide at wizeb.com/blog/ai-chatbot-cost covers that budget.

What Voice Platforms Charge Per Minute

The developer platforms most custom voice agents are built on publish a headline rate, then bill the other parts on top. Vapi lists a platform fee of $0.05 a minute, with speech, model and phone costs passed through at cost, and charges extra for HIPAA support on its enterprise plans (vapi.ai/pricing). Retell AI advertises voice agents from about $0.07 a minute, which covers its voice infrastructure and standard text-to-speech, with the language model billed separately (retellai.com/pricing).

Once every part is added, most production agents land between $0.10 and $0.35 a minute. The low end uses a small, fast model and a standard voice. The high end uses a frontier model, a premium voice and add-ons such as call recording analysis or noise reduction. Always ask for the all-in rate at your chosen configuration, not the headline number.

The Three Ways to Buy a Voice Agent

1. AI receptionist subscriptions: about $50 to $500 a month

Packaged AI receptionists answer your calls, answer common questions, take messages and book appointments into popular calendars. Plans usually include a set number of minutes or calls, with an overage rate above that. They are the fastest way to stop missing calls, and often the right choice for a single-location business with simple calls. The limits are fit and control: they connect to the tools the vendor supports, follow the call flows the vendor designed, and you cannot take the logic with you if you leave.

2. Build it yourself on a voice platform: low build cost, real staff time

Platforms like Vapi and Retell let a technical person assemble an agent in days. You pay the per-minute rate and nothing up front. The hidden cost is time: writing and testing call flows, connecting your calendar and CRM through their APIs, handling edge cases such as callers who interrupt, change their mind or ask for a person, and monitoring calls after launch. If nobody on your team owns that work, the agent drifts out of date quickly.

3. Custom voice agent: $8,000 to $40,000 to build

A custom build is designed around your calls, your systems and your rules, usually on one of those same platforms or on your own stack. The price depends on how many systems the agent must read from and write to, how many call types it handles, whether it needs more than one language, and how much testing your industry requires. Roughly:

• $8,000 to $15,000: answer, qualify and book. One phone line, one calendar, a CRM note after each call and a clean transfer to staff.
• $15,000 to $28,000: look up and act. Order status, rescheduling, quote requests or account questions using live data from two or three systems, plus SMS follow-up.
• $28,000 to $40,000 and up: high-volume or regulated. Outbound calling, payments, several languages, HIPAA or PCI requirements and detailed call analytics.

Running costs for a custom agent are the per-minute rate above plus hosting, monitoring and a maintenance retainer, typically $150 to $600 a month before minutes.

Hidden Costs to Ask About Before You Sign

• Overage rates. Subscriptions look cheap until a busy month. Ask for the exact per-minute rate above the allowance and whether it applies to after-hours calls.
• Transfers and hold time. If the agent transfers a caller to staff, you may keep paying for the minutes while the call rings or waits.
• Number porting. Moving your existing business number to a new carrier can take weeks. Most businesses forward calls instead at first.
• Compliance add-ons. HIPAA agreements, call recording consent and data retention controls are often priced separately.
• Containment that is not resolution. A vendor can report that 70% of calls never reached a person while many of those callers simply hung up and called back. Measure resolved calls, not contained calls.

Set a monthly budget and spend alerts from the first day. Our guide at wizeb.com/blog/ai-agent-cost-budgeting-pay-as-you-go-2026 covers how to budget usage-based AI costs.

Example: Pricing a Voice Agent for a US Home Services Firm

This is an illustrative example, but the numbers are typical. A 40-person HVAC and plumbing company in Ohio takes about 1,800 calls a month. Around 35% arrive after hours or while the two office staff are already on the phone, and many of those callers book with a competitor instead. Calls average three minutes.

• AI receptionist subscription: about $350 a month for the minutes needed. It answers and takes messages well, but cannot see technician schedules in the firm's field service software, so it promises callbacks rather than booking jobs.
• Custom voice agent: about $19,000 to build over six weeks, covering live booking against the dispatch calendar, emergency call routing to the on-call technician, SMS confirmations and testing on recorded calls. Running cost: 5,400 minutes at about $0.16 is roughly $860, plus $250 for hosting and monitoring, so about $1,110 a month.
• Result: if the agent books 40 extra jobs a month at an average $300 ticket and a 40% gross margin, that is about $4,800 a month in gross profit against $1,110 in running cost. The build pays back in about five months.

The subscription is cheaper per month. The custom agent wins because it books jobs instead of taking messages. At a quarter of the call volume, or with no need to check live schedules, the subscription would be the better buy. For a structured way to check payback, see wizeb.com/blog/how-to-measure-ai-agent-roi.

Five Questions to Price Your Voice Agent

1. 1How many calls a month, how long on average, and how many arrive when nobody can answer?
2. 2What share are simple (hours, directions, messages) and what share need the agent to check or change something?
3. 3Which systems hold the answers, and do they have APIs?
4. 4When must a call go to a person, and who takes it?
5. 5Are you covered by HIPAA, PCI or call recording consent rules in your state or country?

Mostly simple calls point to a subscription. Look-ups and bookings across your own systems point to a custom build. If you run a clinic, our separate breakdown at wizeb.com/blog/ai-receptionist-cost-pricing-roi covers that case.

How WizeB Prices Voice Agents

WizeB builds custom voice agents, AI agents and workflow automations for growing businesses in the US, UK and Europe. Every project starts with a free scoping call where we look at your real call volume and call types. You then get a written fixed build price, an all-in per-minute running cost at your chosen model and voice, and a timeline before any work begins. If a packaged AI receptionist covers your calls, we will tell you. Our engineering team works from Kochi, India, which keeps rates well below a typical US or UK agency, and we hold calls in your business hours. We test every agent on recorded calls before it goes live, route simple turns to cheaper models to keep minutes affordable, and you own the call flows, prompts and data. See how we work at wizeb.com/services/voice-ai.