Twilio AI Receptionist That Keeps Your Own Account: Build, Open Source, Platform, or No-Code

The question behind "Twilio AI receptionist that keeps my own account" is a good one, and it is really two questions. Can an AI answer the Twilio number I already own, without porting it to some answering company? Yes, and there are four ways to do it. And which of those four should I pick? That depends almost entirely on one thing: whether you want to build and run software, or you want to answer the phone.

Here are the four paths, with what each asks of you, what it costs per minute of conversation, and what is missing from each. Prices and limits are as published on 21 September 2026. TelBuddy is the fourth path; we have tried to describe the other three the way their own users would.

The four paths at a glance

Per minute of talk time these land closer together than the table suggests. A hundred minutes on Retell is somewhere between $7 and $31 before Twilio's own charges; TelBuddy's 100-minute tier is $19.99 with the receptionist, calendar and transcripts included. The real difference is not the rate. It is who builds the thing and who fixes it at 9pm when it stops answering.

Path 1: build it from Twilio's sample

Twilio publishes a Code Exchange sample that connects a Twilio number to OpenAI's Realtime API over Media Streams. It comes in JavaScript and Python, you supply your Account SID, Auth Token and an OpenAI key, run it on a server (or a tunnel while you test), and point the number's voice webhook at it. Twenty minutes later a caller is talking to a model. It is a genuinely good sample and the fastest way to hear what a realtime voice agent sounds like on your own number.

It is also exactly what it says: a sample. There is no calendar, no transcript, no knowledge base, no transfer rule, no business hours, no dashboard, no record of who called. Each of those is a project. The echo problem alone, where the model hears its own voice through the caller's speaker and interrupts itself, takes real engineering to get right. If you have a developer who wants to own a voice product, this is the honest starting point. If you have a business that needs its phone answered, it is a demo.

Choose it if: the receptionist is the product you are building.

Path 2: open source with LobbyStack

LobbyStack is open-source AI receptionist software with a hosted option. Its own description is that you bring the provider accounts you want to control, including Twilio, an OpenAI-compatible model, Google Calendar and email, and it supplies the product layer on top: answering around the clock, qualifying leads, booking appointments, routing calls, a knowledge base. Hosted pricing is Free, $30 a month for Starter ($24 on an annual plan) and $100 a month for Pro ($80 annual), with the knowledge base growing from 25 MB to 500 MB across the tiers. Self-hosting is free apart from your own servers.

The trade is the same one every open-source product asks for. Self-hosted, you run it, patch it and debug it. Hosted, you pay them and also pay OpenAI and Twilio separately, so a busy month has three bills. Telnyx is not mentioned. For a technical owner who likes the idea of reading the code that answers their phone, it is the most transparent option on this list.

Choose it if: you want the source, you are comfortable operating it, and Twilio is your only carrier.

Path 3: a developer platform (Retell, Vapi)

Retell and Vapi are platforms for building voice agents. You design the agent, write the prompt, wire up functions for anything it needs to do (look up a booking, check a calendar), and connect telephony. Both let you bring your own Twilio or Telnyx: Retell charges $0.015 per minute for US telephony through either and nothing extra for SIP or custom telephony; Vapi lists Twilio, Vonage and Telnyx as telephony options. Retell's all-in rate runs $0.07 to $0.31 per minute depending on the model and voice you pick, with $10 of free credit and no minimum. Vapi charges $0.05 per minute for its platform plus the speech and model costs, which it passes through, with $5 of credit to start and a $999-a-month Pro tier for volume.

These are excellent tools and the per-minute pricing is fair. They are built for developers: the calendar booking is a function you write and host, the transcript goes where you send it, and the "receptionist" is as good as the prompt and the integrations you built. Agencies build small-business receptionists on these platforms and resell them, which tells you where the work lives.

Choose it if: you or an agency will build the agent and you want control over every model and voice.

Path 4: no-code on the dashboard you already use (TelBuddy)

TelBuddy's AI receptionist is a spoken, two-way conversation on your own Twilio or Telnyx number, switched on from the same dashboard that runs your shared inbox and phone menu. There is nothing to host. You give it a name and a personality, paste or upload what it should know (your website pages, price list, PDFs), connect your Google Calendar, set the transfer rule, and turn it on for the hours you want it answering.

What it does on a call, specifically:

• Answers from your material. Hours, prices, services, policies, whatever is in the knowledge base, in a natural voice, without reading a script.
• Books on your real calendar. It checks Google Calendar for actual availability and books during the call, with a travel buffer if you want one, and confirms by text.
• Transfers the calls that need a person. You choose the trigger. On Twilio the transfer can ring the whole team at once; on Telnyx it dials one destination at a time.
• Emails you the transcript after every call, with the caller's number, so nothing said on the phone is lost.
• Works your hours. Business hours decide whether a call goes to the AI, the phone menu, a forward, or voicemail, so the receptionist can take nights and weekends and leave the day to your team.
• Texts too. The same knowledge base answers texts to the number, either drafting replies for a person to send or replying on its own.

Pricing: the AI is an add-on to a core plan. Starter is $19 a month for the dashboard (2 numbers, 2 seats); AI Starter is $19.99 a month with 100 voice minutes included, and tiers run up to 2,000 minutes. Twilio or Telnyx bills you for the carrier minutes at your own rates. The add-on is not part of the seven-day trial; the core plan is.

The limits, honestly: you do not pick the speech model or the voice vendor, you cannot write code inside the agent, and if you need it to call a custom API mid-call, that is a developer platform's job, not ours. What you get in exchange is a receptionist that a non-technical owner can set up on a Tuesday afternoon and change on Wednesday.

Choose it if: you want your Twilio or Telnyx number answered well, today, and would rather not run software.

On Telnyx

Two of the four paths carry over to a Telnyx number without change: Retell and Vapi both list Telnyx telephony, and TelBuddy treats Telnyx and Twilio the same way (the one difference is the transfer, above). Twilio's sample is Twilio-specific by definition, though Telnyx publishes equivalent Call Control examples for developers. LobbyStack does not mention Telnyx. If you chose Telnyx for its rates, the shortlist for a keep-your-own-account receptionist is a platform you build on or TelBuddy. Our Telnyx AI receptionist post goes deeper on that side.

Which one, in one sentence each

• Twilio's sample: you are building a voice product and want to start from working code.
• LobbyStack: you want open source and will run it, on Twilio.
• Retell or Vapi: a developer or agency will build the agent and you want every knob.
• TelBuddy: you want the phone answered on the number you own, with booking and transcripts, and no code.

All four keep your account. That part of the question has a happy answer. The Twilio AI receptionist page walks through the TelBuddy setup step by step, and the per-minute versus per-call pricing post explains why the cost shape matters more than the headline rate.