A2P SMS — Application-to-Person SMS
What is A2P SMS?
A2P (Application-to-Person) SMS is the umbrella term for any text message a business or application sends to a consumer — reminders, one-time passcodes, order updates, marketing — as opposed to P2P texting between individuals. Carriers worldwide treat A2P traffic as a distinct, more heavily regulated category, but the exact registration mechanics are set per country: the US and Canada require A2P 10DLC brand-and-campaign registration, while many other countries instead register an alphanumeric sender ID or apply their own local vetting scheme.
More detail
A2P is the global category; A2P 10DLC is one country-specific implementation of it, covering only US and Canada long-code traffic. A business sending A2P SMS to other countries follows that country's own registration rules instead — see Sender ID.
Carriers distinguish A2P from P2P by traffic pattern (volume, timing, content) as much as by registration status, and unregistered or misclassified A2P traffic is a common cause of filtering or outright blocking, regardless of destination country.
Frequently asked
- Is A2P SMS the same thing as A2P 10DLC?
- No — A2P SMS is the general worldwide category of business-to-consumer texting, while A2P 10DLC is the specific brand-and-campaign registration program carriers in the US and Canada require for A2P traffic sent from long-code numbers.
- How is A2P SMS different from P2P SMS?
- A2P SMS is sent by a business or application to a consumer — reminders, OTPs, marketing, notifications — while P2P SMS is one individual texting another. Carriers apply different throughput, filtering, and registration rules to each because A2P traffic runs at far higher volume and is more heavily policed for spam.
See also
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