What is A2P 10DLC?

An expla­na­tion of mes­sag­ing and com­mon issues with carriers.

Whis­tle pro­vides an Appli­ca­tion to Per­son (A2P) mes­sag­ing plat­form, which dif­fers great­ly from day-to-day Peer to Peer (P2P) mes­sag­ing. “A2P 10DLC” refers to a sys­tem in the Unit­ed States that allows busi­ness­es to send A2P type mes­sages via stan­dard 10-dig­it long code (10DLC) phone num­bers. Car­ri­ers in the US con­sid­er all Whis­tle traf­fic to be A2P.

Common issues

These are instances of car­ri­ers (most com­mon­ly AT&T and T‑Mobile) occa­sion­al­ly block­ing mes­sages from being deliv­ered in the A2P set­ting. Cer­tain car­ri­ers have very strict Spam fil­ters, and this results in mes­sages get­ting caught in these fil­ters tem­porar­i­ly. If you’ve ever seen a ‘Car­ri­er Vio­la­tion’, then you’ve had your mes­sages declined to send to your recipient.

What’s changing?

The good news is that most of the major car­ri­ers are work­ing on rolling out a new A2P 10DLC ‘high­way’, which will allow you to reg­is­ter your busi­ness and pre­vent fil­ter­ing mov­ing for­ward. The antic­i­pat­ed launch date, start­ing with AT&T, is expect­ed to be soon. Once launched, Whis­tle will find out all of the require­ments in order to par­tic­i­pate and include your orga­ni­za­tion as well.

What Do I Need to Do?

Noth­ing right now — hang tight! We are still await­ing final­ized require­ments and pro­ce­dures from our partners. 


Will There Be an Added Cost?

Most like­ly, yes. While this hasn’t been final­ized by the car­ri­ers, and is sub­ject to change, there will most like­ly be a fee asso­ci­at­ed with reg­is­ter­ing your company.


Have More Questions?

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