What is P2P and A2P Messaging?


Jessica Murray


Category About Attributes (per number) Common use cases
P2P (Person-to-Person)

Typically, this is the conventional conversational two-way SMS or MMS messaging between individuals. P2P use cases are very rare.

From CTIA best practices: “Person-to-Person (P2P) generally describes the low-volume exchange of wireless messages between end users... the concept of consistent with typical human operation defines P2P traffic to distinguish P2P from A2P traffic.”

  • 15-60 messages/minute
  • 1,000 messages/day
  • 100 unique recipients
  • Close to 1:1 ratio of inbound messages to outbound messages

Private phone numbers

A2P (Application-to-Person)

One-way SMS to which recipients are not expected to reply. Typically this represents high volume messaging between businesses and individuals.

Some common examples are a logistics company sending delivery statuses and notifications, a dentist’s office sending one-way alerts and reminders, or a financial institution sending PIN codes to individuals either using short codes or long codes.

From CTIA best practices: “A2P traffic is all messaging that falls outside the definition of P2P (i.e., traffic that is not consistent with typical human operation).

  • Bound only by account permissions/rate limits.
  • Typically much higher ratio of outbound messages vs inbound
  • Appointment reminders
  • Shipping & order alerts
  • Outbound mass communications
  • Communication over a platform
  • Chatbots
  • Support conversations

The major difference between the P2P service that Bandwidth offers today on US and Canadian local 10-digit phone numbers and the A2P service using toll-free numbers and long codes is:

  • A2P formally allows TCPA compliant and opted-in use cases for many Application-to-person use cases such as alerts, PIN codes, requested marketing, and automated, high-volume interactions between business/government and consumers.
  • The 1 SMS/number/second message limits imposed in the guidelines for P2P messaging don't apply to A2P messaging services - there are still some limits based on campaign class.
  • The use of a P2P text messaging service requires formal approval by the carriers.  
  • The A2P service is priced differently than P2P messaging services. Please see additional details on the Long Code A2P pricing here.

If your use case requires A2P messaging, please see our toll-free A2P use case best practices or our 10DLC overview.

Questions? Please open a ticket with your Bandwidth Support Team or hit us up at (855) 864-7776!

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