A2P messaging: what it means
DefinitionA2P stands for application to person, meaning text messages sent by software to customers instead of typed by a person on a phone. Appointment reminders, confirmations and on-my-way notices are all A2P, and US carriers apply registration rules to this traffic.[1]
How it works in a service business
The distinction matters because a text typed from your own mobile plan is person to person, while a text fired by scheduling software at scale is A2P. Carriers treat the second kind differently, since it can be used for spam. For an owner, this means automatic messages need a registered business identity and proper opt-out handling. The tradeoff is setup effort against reliable delivery. A common mistake is assuming the software can send texts the moment you sign up. It usually needs a connected messaging account and a completed registration first. Ask any vendor what you must connect and register before reminders can go out, and test with your own phone before announcing the feature to customers.
Example
A tech's personal text to a customer is person to person. The scheduler's automatic reminder the night before is A2P, so it must go out through a registered sender.
Where Apex touches this
In progress
Part of this is built. The rest is not. Status as of 2026-10-07; the badge shows the least-built feature involved.
- CM01Two-way SMS from business number(In progress)
- CM0210DLC / registration handled for you(Rolling out)
- CM03Appointment reminders (SMS/email)(Built, rolling out)
Apex Flow Scheduler is in early access. See how we label status.
Related terms
Sources
- Twilio docs: US A2P 10DLC overview (read 2026-10-07)