Use cases
ReachCell provides real carrier phone numbers — not VoIP — so they pass verification checks that virtual numbers fail. Below are the main patterns developers build with it.
OTP and 2FA receipt
Receive one-time passwords sent by banks, identity providers, and platforms that block VoIP numbers. Subscribe to the sms.received webhook; the body arrives within seconds of delivery.
{
"event": "sms.received",
"data": {
"from": "+14155550100",
"to": "+917822875165",
"body": "Your verification code is 847291"
}
}
WhatsApp registration
ReachCell numbers are real SIM cards registered on carrier networks and can receive the SMS or call used in WhatsApp's phone verification flow. Useful for automation workflows that need WhatsApp Business accounts at scale.
AI agent communication
Give an AI agent a real phone number. The agent can send and receive SMS via the REST API or through the MCP server, which integrates directly into Claude, GPT, and other tool-use frameworks.
Inbound missed-call verification (free-to-caller)
Give a user your ReachCell number. Ask them to call it. When they do, a call.incoming event fires immediately — before they are charged for the call — and a call.missed or call.answered event follows. Use the caller ID to verify ownership of the number at zero cost to the caller.
- User dials your ReachCell number.
call.incomingwebhook fires withfrom= caller's number.- Your server marks the number as verified and (optionally) hangs up via POST /v1/calls/hangup.
- Caller is never connected — call is free on their end.
Outbound call signal delivery
Trigger a call to a customer to deliver a notification. The customer sees your caller ID on their screen — no audio, no answer required. You receive a webhook when the call rings, connects, or is missed.
Number provisioning for users
Provision a dedicated number per user or tenant via POST /v1/numbers/provision. Each number receives its own SMS and call webhooks, enabling multi-tenant communication pipelines over real carrier SIMs.
SMS marketing and notifications
Send SMS to real carriers with real deliverability. Because ReachCell numbers are physical SIMs, they are not on carrier VoIP blocklists. Inbound replies arrive via sms.received webhook for two-way conversations.