What are the best practices for sending SMS messages?

Short description

Amazon SNS offers to send Short Message Service (SMS) text to global audience. However, there are restrictions and prerequisites enforced by the government as well as carriers for sending SMS to certain countries.

When you send SMS messages using Amazon SNS, you can identify yourself to your recipients using the following types of originating identities:

• Sender IDs
• Origination numbers

You must observe the prerequisites for toll-free numbers (TFN), 10-digit long code (10DLC), or sender ID registration to make sure that the SMS delivery is successful.

Resolution

Refer to the documentation on supported Regions and countries to see those that allow message delivery and supported origination identities.

Review the destination country and supported origination identity for sending SMS messages to it. If you use origination identities that aren't supported in the destination county, then the mobile carrier blocks the messages to the recipients.

Countries that require pre-registration of sender ID

A few countries require you to preregister the sender ID. These are:

• Australia
• Belarus
• Egypt
• India
• Jordan
• Kuwait
• Philippines
• Qatar
• Russia
• Saudi Arabia
• Singapore
• Sri Lanka
• Thailand
• Turkey
• Ukraine
• UAE
• Vietnam

Note: Amazon SNS supports Amazon CloudWatch delivery logs for SMS messaging. For information on how to set up CloudWatch logs, see Viewing CloudWatch logs. For troubleshooting the failed SMS delivery requests, send the message IDs to AWS Support.

Countries that require pre-registration of sender ID, TFN, and 10DLC

The following countries require a preregistration of the sender ID, TFN, and 10DLC:

United States

The United States currently supports short codes, 10DLC, and TFN.

US carriers no longer support application-to-person (A2P) SMS messaging over local, unregistered long codes. For high-volume A2P SMS messaging, US carriers offer a new type of long code (10DLC).

You must preregister the toll-free number to send SMS messages to US destinations. This registration takes about 15 business days.

India

By default, Amazon SNS uses International Routing (ILDO) to send SMS messages to India. This means that the messages are charged according to international rates. To send messages using the local rates, you must first register the sender ID before you use it.

Singapore

To send messages to Singapore, Amazon SNS customers must first register the sender ID with the Singapore SMS Sender ID Registry (SSIR).
Note: AWS offers self-registration of the sender ID for Singapore through the AWS Pinpoint console. All the information to do so is available from the link.

China To send messages to China, you must first register your templates through AWS Support for approval.

Senders are required to use a preregistered template for each type of message that they plan to send. If a sender doesn't meet this requirement, then their messages are blocked.

To register a template, open an Amazon SNS SMS case with AWS Support. When you create the case, provide the same information that you provide when you request a sender ID.

For all other countries listed above, create an AWS Support case.

The registration process requires multiple carriers. The timelines for the completion are shared in the documentation for their respective countries. For those countries with only certain origination numbers, refer to the pricing guide for receiving dedicated short codes and long codes.

Mobile phone users generally don't want to receive unsolicited SMS messages. Be sure that you follow best practices for sending SMS from Amazon SNS. These practices can increase customer engagement and prevent the sender from getting blocked or paying penalties.