# An AI receptionist that books appointments on the call > An AI receptionist is a voice agent that answers your business phone, handles common questions from an approved knowledge base, books or moves appointments in your calendar, takes messages and transfers callers to a person when the call needs one. The Method Crew builds it on Vapi or Retell AI with Twilio in 5 to 7 weeks, for $12,000 to $30,000 plus per-minute usage at cost. - Page: https://methodcrew.com/blueprints/ai-receptionist-voice-agent - Last updated: 2026-10-28 - Publisher: [The Method Crew](https://methodcrew.com/) - Blueprint: AI receptionist voice agent A voice agent picks up your calls, answers routine questions from an approved knowledge base, books into your calendar and passes anything it should not handle to a person, with a summary. ## Key facts - Build time: 5 to 7 weeks - Price: $12,000 to $30,000 per project. The low end covers one location and one calendar. Per-minute usage passed through at cost. - Typical stack: Vapi or Retell AI, Twilio, or SIP from your existing phone system, Deepgram for speech recognition, ElevenLabs or Cartesia voices, OpenAI or Anthropic API, Google Calendar, Microsoft 365, Calendly or Cal.com, HubSpot or your CRM for callbacks, n8n for post-call workflows, Slack or SMS for alerts - Runs on your accounts; model and tool usage billed at cost ## How it runs, step by step 1. **Answer the call.** Calls to your existing number forward to the agent all the time, after hours, or when nobody picks up after a set number of rings. The greeting says it is an automated assistant and, where you record, that the call is recorded. 2. **Find the reason.** The agent asks what the caller needs and sorts it into a fixed set of intents: book, reschedule, cancel, question, message or urgent. 3. **Answer from the knowledge base.** Hours, location, parking, published prices and policies are answered only from approved entries. If the answer is not there, the agent says so and offers to take a message. 4. **Book the appointment.** It checks live availability, offers 2 or 3 slots, reads the chosen time back and writes the booking. An SMS confirmation goes out before the call ends. 5. **Take a message.** For anything else it records name, number, reason and urgency, then posts a summary to Slack, email or the CRM as a callback task with an owner. 6. **Hand off to a person.** Callers who ask for a person, sound distressed or describe something urgent are transferred with a short spoken summary. If nobody answers, the agent takes a message and alerts the on-call contact. 7. **Review every call.** Each call is transcribed and tagged by outcome. A weekly review of failed and transferred calls drives updates to the knowledge base and the call policy. ## What the system is made of - **Phone line:** A Twilio number, or SIP from your current phone system, that routes calls to the agent. - **Voice platform:** Vapi or Retell AI runs speech recognition, the model turn and speech output, and lets callers interrupt. - **Call policy prompt:** Defines intents, tone, topics the agent may not discuss and the rules for transfer. - **Knowledge base:** Approved answers to common questions, owned by one person on your team and versioned. - **Booking tools:** Function calls that check availability and create, move or cancel appointments. - **Handoff rules:** Transfer numbers by time of day and intent, with a message fallback when nobody answers. - **Call log:** Transcripts, outcomes, tool calls and cost per call in one table on your account. ## What could go wrong and what stops it - **Questions outside the knowledge base.** The agent answers only from approved entries. When a question is not covered, it says it does not know and takes a message. It gives no clinical, legal or financial advice and quotes only published prices. - **Wrong or double bookings.** Availability is checked at the moment of booking, the date and time are read back, and the caller gets an SMS confirmation. If the calendar API fails, the agent records preferred times and flags the request for staff. - **Callers who need a person.** A request for a person, signs of distress or emergency words trigger a transfer. Anyone describing an emergency is told to hang up and call 911 or local emergency services. After 2 failed attempts to understand a caller, the agent transfers. - **Privacy and recordings.** Transcripts and recordings stay on your accounts with a retention period you set. The agent never reads appointment details back to a caller it has not verified, and its tools only touch the caller's own bookings, so 'ignore your instructions' requests get nothing. ## How does the handoff to a person work? Handoff is designed first, because the calls that matter most are the ones the agent should not finish. In the first stage of every engagement, [Map](https://methodcrew.com/approach#stage-map), we pull a week of call logs or recordings and sort every call into what the agent can handle and what it must pass on. It is the phone version of a [human-in-the-loop](https://methodcrew.com/glossary/human-in-the-loop) design: the agent does the routine part, and a person takes every call that needs judgment. During opening hours, transfers are warm where your phone system allows it. The agent tells the caller it is connecting them, rings the staff number set for that intent and speaks a one-line summary first ("New patient, wants a cleaning next week, prefers mornings"). If nobody answers within the time you set, the call returns to the agent, which apologizes, takes a message and texts the callback request to whoever is on duty. After hours there is usually nobody to transfer to. The agent books what it can, takes messages for the rest and sends anything marked urgent to an on-call number. It never promises a callback time your team has not agreed. Every transfer is logged with its reason. When the same question keeps causing transfers, that is a gap in the knowledge base, and it goes on the weekly fix list. The agent sits inside a [voice AI build](https://methodcrew.com/services/voice-ai-agents), and its knowledge base follows the same rules as our [RAG knowledge systems](https://methodcrew.com/services/rag-knowledge-systems). ## What does an AI receptionist cost to build and run? The build is a fixed price between $12,000 and $30,000. The low end covers one location, one calendar and a knowledge base of about 50 questions. Several locations, a practice or property management system with a harder API, bilingual calls or outbound reminders push it toward the top. Most builds take 5 to 7 weeks, including 2 weeks of supervised live calls. That price covers the full receptionist: answers from the knowledge base, booking, messages and transfers. If you need only one call flow, such as after-hours booking, that is a smaller [voice AI build](https://methodcrew.com/services/voice-ai-agents) at $6,000 to $15,000, and it can go live in 3 to 4 weeks. Usage is billed per minute and passed through at cost on your accounts. Retell AI publishes pay-as-you-go pricing of $0.07 to $0.31 a minute, depending on the model and voice ([Retell AI pricing](https://www.retellai.com/pricing), checked October 2026). Other platforms, Vapi among them, bill the platform and the speech, model and phone providers as separate lines, so compare all-in figures. A worked example: 1,500 call minutes a month at $0.12 a minute is $180 in usage, plus Twilio number and SMS fees. The larger running cost is attention. Someone should read the weekly report of failed and transferred calls for the first 2 months. If nobody on your team has the time, an [AI ops monitoring plan](https://methodcrew.com/services/ai-ops-monitoring) at $1,500 to $5,000 a month covers call review, knowledge base updates and model changes. ## When is an AI receptionist the wrong choice? If your phone rings fewer than about 10 times a day and someone is always there to answer, keep the person. The agent will work, but the savings will take years to cover the build. It is also wrong for calls where the conversation is the service. Clinical triage, a tenant with a burst pipe at 2am, a legal intake that needs a conflict check: these need a trained human, and the agent's only job is a fast, clean transfer. If most of your calls look like that, an answering service with trained staff is the better buy. Two technical blockers come up in scoping. Booking needs an API. If your scheduling system has none, the agent can only take a request for a person to confirm, which removes much of the benefit. And if nearly every call is the same request, such as booking a viewing, a short phone menu that texts the caller a booking link costs far less. We will say so in the scoping call and build that instead. This blueprint covers inbound calls. Outbound reminders are a separate decision: the FCC's February 2024 ruling brought AI-generated voices under the Telephone Consumer Protection Act ([FCC-24-17](https://docs.fcc.gov/public/attachments/FCC-24-17A1.pdf)), so we add them only after your counsel reviews consent. For the wider choice between agents, workflows and chatbots, read [AI agents vs automation vs chatbots](https://methodcrew.com/insights/ai-agents-vs-automation-vs-chatbots). ## Common questions about this build ### Will callers know they are talking to AI? Yes, because we set the greeting to say so, for example: you have reached the clinic's automated assistant, and this call is recorded. We recommend disclosure everywhere. Several US states, California among them, require every party to consent to a recording, so the greeting covers that as well. Your counsel confirms the exact wording for the places you operate. ### Can the AI receptionist transfer a call to a real person? Yes. Any caller who asks for a person, sounds upset or describes something urgent is transferred to the number set for that situation, with a short spoken summary first where your phone system supports warm transfer. If nobody answers, the agent takes a message and alerts your on-call contact by SMS or Slack. ### Can we keep our existing phone number? Yes. The usual setup forwards calls from your current number to the agent, either all the time, after hours or when nobody picks up after a set number of rings. The number stays with your current carrier. We can port it to Twilio if you want everything in one account, but that is rarely needed. ### Which calendars and booking systems can it use? Google Calendar, Microsoft 365, Calendly and Cal.com are straightforward because their APIs support checking availability and creating bookings. Practice management, property management and salon systems work when they expose an API for availability and appointments. We confirm that in the scoping call. Without an API, the agent takes booking requests for staff to confirm. ### Can a medical or dental practice use an AI receptionist? Yes, with conditions. If calls involve protected health information, every vendor in the chain must sign a business associate agreement under HIPAA, and some voice platforms offer that only on enterprise plans. The agent books, reschedules and answers practice questions. It gives no clinical advice and tells anyone describing an emergency to hang up and call 911. ### Can it make outbound calls too? It can place reminder and follow-up calls, but outbound carries more legal risk. In February 2024 the FCC ruled that AI-generated voices count as artificial voices under the Telephone Consumer Protection Act, so most such calls need the recipient's prior express consent. We build outbound flows only after your counsel has signed off on consent and calling rules. ## Services that build and run it - [Voice AI and call automation](https://methodcrew.com/services/voice-ai-agents): Phone agents on your existing number that book into your calendar and hand off to staff. $6,000 to $40,000 per project. - [AI ops monitoring and improvement](https://methodcrew.com/services/ai-ops-monitoring): Quality checks, cost control and model updates for live AI systems. $1,500 to $5,000 per month. ## Sectors where it fits - [Healthcare and clinics](https://methodcrew.com/industries/healthcare-clinics): Front desks in busy practices spend the day on the phone and the evening on paperwork. We build voice agents and intake automation that take the routine part of both, and hand anything clinical to your staff. - [Real estate](https://methodcrew.com/industries/real-estate): Portal leads go cold while agents are at showings, and tenants email the office about every dripping faucet. We build the systems that answer leads in minutes, book showings and keep property managers out of the maintenance inbox. ## Next step Request a 30-minute scoping call: https://methodcrew.com/contact. Or email contact@methodcrew.com.