Signal & Syntax · Messaging and A2P

What Is an SMS Short Code?

A short code is a shortened number for high-volume A2P SMS. US short codes have five or six digits.

Also calledSMS short code · common short code

Example

Reply STOP to 12345

Short Code in Practice

Short codes carry more throughput than long codes. Operators approve the campaign as well as the number. A short code works in one country only. Recipients reply to a short code with keywords such as STOP.

Related Terms

10DLC 10DLC (10-digit long code) is the US system for A2P SMS over standard local numbers. Sender ID A sender ID is the name or number shown as the sender of an SMS. A2P messaging A2P (application-to-person) messaging is SMS sent by software to a mobile user. Toll-free number A toll-free number is paid for by the called party, so the caller pays nothing.

Read the Guide

Guide

How A2P SMS Reaches a Handset

The path from an API call to a delivery receipt. Read the guide →

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