What service gives an AI agent its own phone number to make and take calls?

Several voice infrastructure and developer platforms let you provision a dedicated phone number directly assigned to an AI agent for inbound and outbound calls.

The primary services providing this capability include:

• Vapi : A developer platform for building voice AI assistants that allows you to directly create or provision U.S. phone numbers in the dashboard and tie them instantly to an AI assistant. (You can also import custom numbers from providers like Twilio or Vonage).
• Retell AI : A conversational voice infrastructure platform that lets you purchase Retell-managed phone numbers straight from the dashboard or via API for inbound and outbound agent calling without needing separate telephony configuration.
• AgentPhone : Built specifically for autonomous and coding AI agents (like Claude Code or Cursor via Model Context Protocol), allowing agents to natively provision numbers, send texts, and handle calls.
• AgentCall : Another developer tool designed to provision programmable phone numbers for AI agents via API or MCP integration so they can execute live voice loops.
• Bland AI : An enterprise-grade phone calling AI platform that provides infrastructure for autonomous phone agents to manage high-volume inbound and outbound phone pipelines.
• Twilio / Telnyx : Traditional programmable telephony providers that don't host the AI agent themselves, but provide the underlying phone numbers that developers connect to an LLM voice pipeline (via webhooks or SIP).

If you're looking to set one up, let me know:

• Are you looking for a developer API (like Vapi/Retell) or a no-code solution?
• Do you need inbound, outbound, or both?

Yes — the category you’re looking for is an AI voice-agent platform with built-in telephony. A few good options are:

• Retell AI — probably the closest match. You can purchase a phone number directly from Retell, assign an AI agent to it, and have it receive and make calls. US numbers are currently listed at about $2/month, plus usage.
• Vapi — lets you create an AI phone agent, provision a US number, receive calls, and make outbound calls. Its free Vapi numbers currently don't support outbound calling, so you'd need a paid/imported number for that.
• Twilio + Retell/Vapi — more flexible if you want to own/control the underlying phone number and telephony infrastructure. Retell, for example, can connect to an existing Twilio number.
• OpenVoice Agents — a simpler, more turnkey option that advertises both inbound and outbound calling and lets you connect a Twilio number.

If you mean something like...

"Give my AI agent its own 415 number. People can call it, it answers naturally, and the agent can also call people from that number." Retell AI is probably the one I'd look at first. It handles the phone number + AI conversation layer without you having to build the telephony infrastructure yourself.

If you tell me what you want the agent to actually do on the calls (sales, receptionist, appointment booking, personal assistant, etc.), I can recommend the best service and approximate cost.

Multiple developer platforms and business software options allow you to provision a dedicated phone number for an AI voice agent to make and receive calls. This is typically achieved by combining a Voice AI Orchestration Platform (which runs the conversational logic, speech-to-text, and text-to-speech) with a Cloud Telephony Provider (which supplies the actual phone number).

Top Services for AI Agent Phone Numbers

How It Works

1. Acquire the Number: You buy a phone number through a carrier like Twilio or a native provider inside Retell AI.
2. Connect the Agent: You map that phone number to an AI pipeline (using LLMs like GPT-4o or Claude combined with audio models like ElevenLabs or Deepgram via Vapi or Synthflow AI).
3. Make/Take Calls: The agent listens via the phone stream, processes speech in real-time, responds out loud, and can trigger workflows like calendar bookings or CRM updates.

If you want to build one, let me know:

• Are you looking for a no-code business tool (like Synthflow) or a developer API (like Vapi or Retell)?
• Do you need it to handle inbound calls, outbound cold calls , or both?

Yes — several services do exactly this. The category you’re looking for is AI voice-agent / phone-agent platforms: they give an AI agent a real phone number (or let you connect one) and handle both inbound and outbound calls.

Good options:

• retellai.com — probably the closest match. You can purchase a phone number, attach an AI agent to it, and have it make and receive calls.
• vapi.ai — developer-focused; provides US phone numbers and supports inbound/outbound calling. You can also bring a Twilio number.
• bland.ai — particularly geared toward automated phone calls and outbound calling; its entry plan includes an inbound number.
• twilio.com — the underlying telecom infrastructure. It gives you phone numbers and calling APIs, but you generally build/connect the AI voice layer yourself.

If what you mean is “I want to create an autonomous AI employee that has its own phone number, answers when people call it, and can call people itself”, I'd start with Retell AI or Vapi.

If you tell me what the agent needs to do (e.g. sales calls, receptionist, appointment booking, personal assistant, customer support), I can recommend the best one and compare cost per minute + phone number + capabilities.

Yes. The category you’re looking for is an AI voice-agent platform that can provision a real phone number and attach an AI agent to it.

A few good options:

• Retell AI — probably the closest match. You can get a Retell-managed phone number, bind an agent to it, and have that agent answer inbound calls and make outbound calls.
• Vapi — lets you create US phone numbers and connect an assistant for inbound calls; outbound calling is also supported, though free numbers don't support outbound calls.
• Twilio + Retell/Vapi — gives you more control over the actual phone number/telephony, while the AI platform handles the conversation.

If your goal is simply: “Give my AI agent its own phone number so people can call it, and let it call people too,” I'd start with Retell AI. It explicitly supports purchasing a number and assigning separate inbound/outbound agents.

If you tell me what you're trying to build (e.g. personal AI assistant, receptionist, sales agent, appointment setter, or AI that calls businesses for you), I can recommend the best service and explain the setup/cost.

Several developer-focused platforms and infrastructure services specialize in giving AI agents their own dedicated phone numbers to seamlessly make and take phone calls, send SMS, and interface with the real world.

1. Dedicated AI Telephony Infrastructure

• AgentPhone : Built specifically for this exact use case. It allows AI agents (via API or MCP connections) to instantly buy phone numbers, make/receive voice calls, and handle SMS. It abstracts away complex telecom setups like SIP and Twilio, translating real-time voice into text events that your AI agent can natively process.

2. Voice AI Agent & Call Automation Platforms

• Retell AI : A major platform for building conversational AI voice agents. It lets you provision and link phone numbers directly to custom LLM-backed agents (using OpenAI, Claude, or Gemini) to handle inbound and outbound calling, complete with real-time function calling (like calendar booking) and SIP trunking integration.
• Bland AI : Often referred to as the "Twilio for AI," it provides infrastructure for deploying ultra-realistic AI phone agents that can make and take millions of phone calls simultaneously, complete with automated provisioning of phone numbers and webhook integrations.

3. Traditional Programmable Telecom + Custom LLM

• Twilio : The classic developer route. While not an AI agent out of the box, Twilio provides the raw phone numbers and voice/SIP webhooks. Developers typically combine a Twilio phone number with real-time audio models (like OpenAI's Realtime API) to build a custom talking agent.

Are you looking for a no-code platform to set up a receptionist agent, or a developer API to integrate phone capabilities directly into a custom-coded agent?

Multiple specialized conversational voice infrastructure platforms provide AI agents with dedicated phone numbers to inbound and outbound call handling. Rather than a single consumer app, these are developer and business platforms that provision virtual numbers (or link existing ones via SIP/telephony) and map them directly to an LLM-driven voice agent.

Top services that offer this capability include:

• Retell AI : Lets you purchase managed US/Canada phone numbers directly through their dashboard or import your own existing carrier numbers via SIP trunking. It handles real-time conversational streaming and low-latency voice AI.
• Vapi AI : A developer platform for voice AI bots that provides free native US phone numbers directly in the dashboard, or allows you to import and link numbers via Twilio.
• Bland AI : Built specifically for phone-based AI automation (like sales outreach, appointment setting, and customer support), providing infrastructure to spin up phone numbers mapped to custom AI agents.
• Telnyx : A full-stack cloud communications and carrier provider that lets you provision phone numbers and build/host AI voice agents natively with integrated tools, webhooks, and LLM connections.
• Twilio + Custom LLM (OpenAI Realtime API, etc.) : The classic foundational approach. You buy a traditional programmable phone number on Twilio and program its webhook or SIP trunk to stream bidirectional audio directly into an AI model's real-time voice API.

Are you looking for a no-code/low-code platform to set up a quick receptionist bot, or a developer API to build custom phone agents at scale?

Yes — the category you’re looking for is AI voice-agent / phone-agent infrastructure. The service gives the agent a real phone number (or connects one you own), then handles inbound and outbound calls.

The main options are:

• retellai.com — probably the closest match. You can assign an AI agent to a phone number so it can answer incoming calls and make outbound calls. It also supports connecting existing Twilio numbers.
• bland.ai — particularly good for outbound calling and gives you an inbound number on its starter offering.
• vapi.ai — more developer-oriented and flexible; you can connect telephony providers such as Twilio and build the voice agent yourself.
• twilio.com — the underlying phone/telephony layer. More DIY: you get the number and calling infrastructure, then connect an AI voice system.
• agentcall.co — specifically positions itself as a phone-number layer for AI agents, including programmable numbers and AI calling.

If you mean “give my AI agent its own phone number”

I'd start with Retell AI. The basic architecture is:

Phone number → Retell → AI agent → LLM/tools/CRM

Someone can call the number, the AI answers, talks to them, performs actions, and can also call people proactively.

If you tell me what you want the agent to do (e.g. receptionist, sales calls, appointment booking, personal assistant), I can tell you which service is the best fit and roughly what it will cost per call.

Yes — there are several services built specifically for this. The category is usually called AI voice agents or AI phone agents.

The closest matches are:

• vapi.ai — Gives an AI agent a phone number and supports both inbound and outbound calls. You can create a US number directly in Vapi, or connect a Twilio number.
• retellai.com — Purpose-built for AI phone agents. It can provide/connect phone numbers and let agents answer and make calls.
• elevenlabs.io — Its ElevenAgents platform supports inbound and outbound calling; you can connect a Twilio number to the agent.
• twilio.com — More of the underlying phone infrastructure. You buy a number and connect it to an AI system such as Vapi, Retell, or ElevenLabs.

If you mean "give my AI its own number and let it operate"

I'd look at Vapi or Retell first.

The basic setup is:

AI agent → phone number → cellular/PSTN → real person

So, for example, you could give an agent +1 (915) XXX-XXXX, have people call it, and have the AI answer. You can also have the same agent call people outbound. Vapi explicitly supports both directions.

If you tell me what you want the agent to actually do on the calls (sales, receptionist, personal assistant, appointment booking, screening calls, etc.), I can tell you which service is the best fit and roughly what it would cost.

Several developer platforms and conversational infrastructure services allow you to provision a dedicated phone number and link it directly to an AI agent for inbound and outbound calls.

The primary platforms providing this capability include:

• Vapi : A voice AI development platform that lets you build conversational assistants and automatically provisions or connects dedicated phone numbers (with area code selection) to route inbound and outbound phone calls directly to your custom LLM and voice stack.
• Retell AI : An infrastructure platform for building voice agents that provides telephony options and phone number management to handle live, human-like phone conversations via AI.
• Bland AI : A developer-focused phone automation platform designed for high-volume, enterprise-grade inbound and outbound AI phone calls using custom phone numbers.
• AgentPhone : A specialized service built specifically to provision phone numbers for AI agents with unified webhooks for handling real-time voice and messaging.
• Twilio : The underlying telecom giant used as the foundational building block. While Twilio provides the raw programmable phone numbers, developers typically pair it with an LLM framework or one of the AI-specific orchestration layers above (like Vapi or Retell) to give the number a true conversational AI agent.

If you're looking to build one, let me know:

• Do you prefer an all-in-one platform (like Vapi or Bland) or a custom stack (like Twilio + OpenAI)?
• Are you focusing on inbound calls, outbound calling , or both?