Application-to-Person messaging is a different job from person-to-person SMS: registered sender IDs, automatic opt-out handling, and delivery you can actually verify. Built into every 6X wholesale account.
One-time codes for login, sign-up, and 2FA — sent via our Phone Verification API with flat per-verification pricing by country, or as plain SMS.
Order confirmations, shipping updates, appointment reminders, payment receipts — the messages customers expect and actually want.
Bulk promotional sends to an opted-in list, with automatic suppression the moment someone replies STOP — no manual list management.
Register your alphanumeric sender ID once, and set per-destination-country overrides for markets that require a specific pre-registered ID.
A reply of STOP or UNSUBSCRIBE suppresses that number for your account instantly — real compliance infrastructure, not a policy you have to enforce yourself.
Automatic detection of volume spikes, off-hours sending, and high-risk destinations — protecting your account and your sender reputation.
Real-time delivery status and inbound replies pushed to your server the moment they happen — build automation on top instead of polling.
A2P (Application-to-Person) is messaging sent by software to real customers at volume — OTPs, alerts, campaigns — and comes with real compliance requirements (sender ID registration, opt-out handling) that person-to-person SMS doesn't.
For many destinations, yes — some countries require a specific pre-registered alphanumeric sender ID. You can register yours once and set per-country overrides for markets that need it.
A reply of STOP or UNSUBSCRIBE suppresses that number for your account instantly and automatically — real compliance infrastructure, not a policy you have to enforce yourself, and it's scoped per account so it never affects another 6X customer's sends.
Automatic detection of volume spikes, off-hours sending patterns, and high-risk destinations — protecting your account and your sender reputation without you having to monitor it manually.
Yes — the 6X API's Phone Verification endpoint supports both SMS and voice delivery of one-time codes, with flat per-verification pricing by country.
A2P runs on the same account and rate list as general SMS — it's the same underlying termination, just with the sender ID/compliance layer required for application-to-person traffic.
Register free, register your sender ID, and start sending — OTP, alerts, or campaigns.
Sending general person-to-person SMS instead? See our Wholesale SMS page for SMPP termination without the A2P-specific sender rules.
Wholesale SMS →Want to verify sender-ID delivery before a real campaign goes out? 6X Route Inspector independently audits SMS routes for delivery and sender-ID integrity — even routes outside 6X.
See Route Inspector →