AgentPhone: the YC-backed agent phone API#
AgentPhone is the agent-native number service with the clearest backing: Y Combinator lists it in its Spring 2026 batch. It gives each AI agent its own US or Canadian phone number that can place and answer calls and send texts, controlled through a REST API or an MCP server. Everything below is from AgentPhone's own pricing page and llms.txt, read November 11, 2026.
| Item | AgentPhone price or detail |
|---|---|
| Phone number | $3.00 per number per month (US and Canada); a specific area code costs $75 one-time |
| Voice, your own agent (webhook mode) | $0.13 a minute: caller speech is transcribed and sent to your webhook, your agent replies |
| Voice, AgentPhone's hosted agent | $0.22 a minute: you give it a system prompt, no server needed |
| Texting | SMS $0.02 per outbound segment, MMS $0.03; outbound SMS to about 200 countries |
| iMessage | From $150 a month per inbound-only line, $250 for a dedicated line, with RCS fallback; RCS and WhatsApp listed as beta |
| SIP trunk | On request; inbound $0.00374 a minute |
| Call recording | $5 a month add-on |
| MCP server | Hosted at mcp.agentphone.ai with 28 tools (numbers, SMS, calls, agents, conversations, contacts, webhooks); also a local npm package |
| Agent self sign-up | The agent calls a sign-up endpoint with its human's email; the human receives a 6-digit code, and nothing is provisioned until it is entered |
| Free credit | $5 on sign-up, which AgentPhone says covers the first month of one number plus some usage; no separate sandbox |
- What it does well: the two voice modes let you start with the hosted agent and move to your own model later without changing the number; one webhook event covers both calls and texts; the self sign-up flow keeps a human in the loop before anything is bought.
- Weak spots: $3 a number is three times Telnyx's $1, and $0.13 a minute for a webhook call is well above raw carrier rates (Telnyx and Plivo charge roughly $0.005 to $0.012 a minute for the call itself), so you pay for convenience. iMessage lines are expensive. Numbers are US and Canada only. There is no sandbox: API keys work on live numbers from day one. As a 2026 startup it has no long track record; check porting and number-ownership terms before you publish a number.
AgentPhone alternatives and clones, compared#
At least eight more services launched the same idea in 2025 and 2026. We opened each one on November 11, 2026, and read its own pricing, docs or llms.txt. The last column says how much we could verify.
| Product | Number | Voice | Texting and channels | Agent tooling | How verified |
|---|---|---|---|---|---|
| AgentPhone (YC Spring 2026) | $3/month | $0.13/min webhook, $0.22/min hosted | SMS $0.02, MMS $0.03; iMessage $150 to $250/month | MCP (28 tools); self sign-up; $5 credit | Pricing page and llms.txt |
| Dial | Virtual $3/month; local $35; all channels $300 | $0.13/min self-hosted, $0.22/min managed | SMS from $0.02 (US) to $1.00; iMessage +$215/month; WhatsApp +$100/month, by invitation | MCP; agent signs up through a skills file, code by email or SMS; $5 credit, no card | pricing.md and llms.txt |
| AgentCall | $2/month local, $2.50 toll-free; Pro plan $19.99/month plus usage | $0.035/min plain calls; AI voice $0.40/min managed or $0.10 with your own AI key | SMS $0.015 out, $0.008 in; OTP code extraction | MCP with 62 tools; 72-hour trial after card verification | Pricing page and llms.txt |
| KaiCalls | Plans $10, $79 and $349/month; extra lines $15/month | Included in plans | SMS, WhatsApp | MCP and REST; checks consent, do-not-call lists and calling hours before each call | Agent API page and llms.txt; per-number API price not published |
| Saperly | From $2/month | $0.13/min webhook, $0.26/min hosted, same rate to any country | SMS $0.02 (US/Canada) to $0.05 | MCP plus connectors for Claude Code and OpenClaw; says it handles disclosure, consent and 10DLC; $5 credit | Homepage only (self-reported) |
| KwickPhone | $5/month | All-in AI talk time $0.49, $0.39 or $0.29/min by tier | Not the focus | One POST returns a live number with the AI already answering; in-call card payments; English, Spanish, Chinese; no MCP stated | API page |
| AgentLine | Hosted plans $20, $50, $200/month; extra numbers $3 | Overage $0.12/min | SMS, overage $0.02 | MCP; open-source repo (MIT, last commit October 21, 2026); free trial 7 days or 10 minutes | Site and GitHub |
| AgentNumber | $5 one-time, paid in USDC on Base | $0.05/min, runs on Vapi | SMS $0.02 | Says no KYC and no sign-up; US only | Thin: homepage claims only |
| Spenza | No price published | No price published | Says SMS, voice, audio streams, eSIM, porting, 40+ countries | Email sign-up form only | Thin: homepage claims only, no pricing or docs |
| AgenticCalling | Not checkable | Not checkable | Not checkable | Not checkable | Offline: returned HTTP 503 (hosting suspended) on November 11, 2026 |
What separates them#
- Closest to AgentPhone: Dial matches its voice prices exactly ($0.13 and $0.22) and its $3 entry number, and adds paid WhatsApp; Saperly matches the $0.13 webhook rate and charges the same per minute to any country. If AgentPhone's US/Canada limit is a problem, those two are the first to check.
- Channels. AgentPhone and Dial sell iMessage lines (expensive: $150 to $250 and $215 a month) and WhatsApp. That is their clearest difference from a carrier.
- Who runs the voice AI. The $0.13 rates (AgentPhone, Dial, Saperly) send the call to your own agent through a webhook; the higher hosted rates include their model and voice. AgentCall's $0.035 plain-call rate is a raw call with no AI.
- Compliance tooling. KaiCalls checks consent, do-not-call lists and calling hours on the server before each call. Saperly says it handles disclosure, consent and 10DLC, which we could not verify beyond its homepage.
- KYC. AgentCall verifies a card before the trial; AgentNumber advertises no KYC at all. Carriers block numbers that send unverified traffic, so a no-KYC number is a deliverability and abuse risk, not just a convenience.
- Self-hosting. AgentLine is the only one with an open-source (MIT) stack you can run on your own SignalWire account.
- Age. All of these are young. Read the terms on number ownership and porting before an agent's number ends up on business cards.
Voice agent platforms that hand an agent a number#
| Platform | Number | Voice price | Limits worth knowing |
|---|---|---|---|
| Bland AI phone number | Included: $9.99 first month, then $19.99/month, unlimited US/Canada calls and texts under fair use | Developer plan $0.14/min | Fair use: 1 call at a time, 20 calls an hour, 50 a day, 1,000 minutes a day, 100 texts a day. MCP server; the agent creates a sign-up link and a human approves before any charge |
| Vapi | 1 free US number on the free tier (5 on Core, 10 on Pro) | $0.05/min hosting plus model and voice providers | Free numbers are inbound only, US area codes only, cannot run outbound campaigns or be ported out |
| Retell AI | $2/month local, $5/month toll-free (US/Canada) | $0.055/min voice engine plus model, voice and telephony | Card required to buy a number; toll-free inbound $0.06/min; SMS add-on $20/month |
| ElevenLabs Agents | Import a Twilio number or a SIP trunk | $0.08/min plus the LLM | No ElevenLabs telephony fee; you need a carrier account |
Bland's $19.99 number is the simplest offer here for a personal or single-purpose agent: a flat price with no per-minute meter, at the cost of strict daily caps. For a production agent, Vapi or Retell plus a carrier number scales further. Our voice agent platform comparison has the full per-minute breakdown.
Carriers: the cheapest primitive#
- Telnyx: local or toll-free numbers from $1.00 a month (plus $0.10 a month to enable texting), voice AI agent at $0.05 a minute, SIP inbound from $0.0032 a minute, SMS from $0.004. It has the most agent-ready carrier setup we found: a bot sign-up endpoint (the agent passes a test meant for an LLM, then a human gets a sign-in link) and a remote MCP server. Agent-created accounts start as limited trials; Telnyx says full KYC applies later.
- Twilio: $1.15 a month for a local number, $2.15 toll-free; $0.0085 a minute to receive calls, $0.014 to make them; Media Streams $0.0044 and ConversationRelay $0.07 a minute for AI. Twilio's MCP server (public beta since May 7, 2026) searches Twilio's docs only and is read-only: it cannot buy numbers or place calls.
Several agent-native APIs run on top of carriers or platforms (AgentLine on SignalWire, AgentNumber on Vapi) and add the agent-friendly layer: MCP tools, self sign-up, iMessage. You pay for that layer: AgentPhone's $3 number costs three times Telnyx's $1. For carrier-by-carrier prices, see our Twilio alternatives for AI voice agents.
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The rules: what changed for AI calls and texts#
US rules decide what an agent may do with its number. This is a summary, not legal advice; the sources are linked so you can read them yourself.
- AI voices are "artificial" voices (February 2024). The FCC's declaratory ruling FCC 24-17, adopted February 2 and released February 8, 2024, says the Telephone Consumer Protection Act's limits on "artificial or prerecorded voice" calls cover AI-generated voices. Outbound AI calls therefore need the called party's prior express consent, and prior express written consent for telemarketing. Sources: FCC 24-17 (PDF) and the FCC announcement (fcc.gov blocks automated fetches; we confirmed the page through search). The rule text itself is 47 CFR 64.1200 (ecfr.gov also blocks automated fetches; confirmed through search and the FCC's own citations).
- The one-to-one consent rule is dead (January 2025). The FCC's 2023 rule requiring consent to name one seller at a time was vacated by the Eleventh Circuit in Insurance Marketing Coalition v. FCC on January 24, 2025. The FCC had postponed it the same day (DA 25-90, PDF).
- Consent revocation: new rules take effect November 25, 2026. Most of the 2024 revocation rules (opt out "by any reasonable means", honoured within 10 business days) took effect April 11, 2025. The stricter "revoke-all" provision was delayed twice and never took effect. FCC 26-67, adopted September 30 and released October 1, 2026, replaces it: an opt-out from an informational call can be limited to that category of call (a marketing opt-out still covers all marketing), and callers may designate one exclusive opt-out method: a keypress or voice command on the call, a reply keyword, or a named website or phone number. Sources: FCC 26-67 (PDF) and the Federal Register notice (published October 26, 2026, effective November 25, 2026). For an AI agent, the practical step is an in-call opt-out ("say stop calling me") that you announce and honour.
- AI disclosure is still only a proposal. The FCC's August 2024 proposal to define "AI-generated calls" and require disclosure (FCC 24-84, PDF) has no final rule in the Federal Register as of November 11, 2026.
- Caller ID authentication. Since September 18, 2025, providers that use a third party to sign calls under STIR/SHAKEN must make the attestation decision themselves and sign with their own certificate (Federal Register 2025-15809). Ask any number provider which attestation level your agent's outbound calls get.
- Texting costs more since August 2025. Texts from US local numbers need A2P 10DLC registration with The Campaign Registry. Its fee sheet, a PDF on campaignregistry.com (revision dated August 1, 2025), raised fees; Twilio's pass-through table lists a $4.50 brand registration ($46 with secondary vetting at $41.50), $15 vetting per campaign and $1.50 to $10 a month per campaign. If you give numbers to many businesses, each business is a separate brand.
Inbound-only agents (a receptionist that answers calls) avoid most of this. The moment an agent dials out or texts first, consent, revocation and 10DLC apply. Our AI outbound calling guide covers the outbound side in more depth.
Which to pick#
- A personal agent that calls restaurants, doctors or shops for you: Bland's $19.99 number (flat price, daily caps) or AgentPhone / Dial if you run your own agent and want per-minute pricing.
- An agent that must text over iMessage or WhatsApp: AgentPhone or Dial, budgeting $100 to $250 a month for those channels.
- A product that gives numbers to many customers: a carrier (Telnyx for the agent sign-up and MCP tooling, or Twilio) so you control KYC, 10DLC brands and attestation yourself.
- Outbound calling at any scale: KaiCalls' server-side consent checks are worth a look, but consent records remain your responsibility whichever provider you use.
- An inbound phone agent for a business: Retell or Vapi for developers; a ready-made AI receptionist otherwise. If you want one built from a website in minutes, see URL-to-receptionist tools compared.
Frequently asked questions#
How can an AI agent get its own phone number?#
Through an API. Agent-native services such as AgentPhone, Dial and AgentCall sell numbers for $2 to $5 a month with MCP servers; Bland sells an AI phone number for $19.99 a month; Vapi gives one free inbound US number; Retell sells numbers for $2 a month; carriers such as Telnyx ($1 a month) and Twilio ($1.15) sell them directly.
Can an AI agent sign itself up for a phone number?#
Partly. AgentPhone, Dial, Bland and Telnyx all have sign-up flows an agent can start, but each one sends a code or approval link to a human before the account or charges go live. Telnyx's agent-created accounts start as limited trials, with full KYC later.
Is it legal for an AI agent to make phone calls?#
In the US, yes with consent. The FCC ruled in February 2024 (FCC 24-17) that AI-generated voices are artificial voices under the TCPA, so outbound AI calls need prior express consent, and written consent for telemarketing. Revised opt-out rules (FCC 26-67) take effect November 25, 2026. Inbound calls that the agent answers are not restricted this way.
Do AI agents need 10DLC registration to send texts?#
Yes, for text messages from a US local number. Each brand and campaign must be registered with The Campaign Registry; through Twilio that costs $4.50 per brand ($46 with vetting), $15 per campaign and $1.50 to $10 a month per campaign.
What is the cheapest phone number for an AI agent?#
Vapi's free inbound-only US number, then Telnyx at $1 a month and Twilio at $1.15. Among agent-native APIs, AgentCall starts at $2 a month and AgentPhone and Dial at $3.