SMS overview


SMS and PSTN capabilities depend on the phone number you use and the country/region that you're operating within as determined by your Azure billing address. For more information, visit the Subscription eligibility documentation.

Azure Communication Services enables you to send and receive SMS text messages using the Communication Services SMS SDKs. These SDKs can be used to support customer service scenarios, appointment reminders, two-factor authentication, and other real-time communication needs. Communication Services SMS allows you to reliably send messages while exposing deliverability and response metrics.

SMS features

Key features of Azure Communication Services SMS SDKs include:

  • Simple setup experience for adding SMS capability to your applications.
  • High Velocity message support over toll free numbers and short codes for A2P (Application to Person) use cases in the United States.
  • Bulk Messaging supported to enable sending messages to multiple recipients at a time.
  • Two-way conversations to support scenarios like customer support, alerts, and appointment reminders.
  • Reliable Delivery with real-time delivery reports for messages sent from your application.
  • Analytics to track your SMS usage patterns. See SMS insights for details.
  • Opt-Out handling support to automatically detect and respect opt-outs for toll-free numbers and short codes. Opt-outs for US toll-free numbers are mandated and enforced by US carriers. See opt-out handling FAQ for details.

Sender types supported

Sending SMS to any recipient requires getting a phone number. Choosing the right number type is critical to the success of your messaging campaign. Few of the factors to consider when choosing a number type include destination(s) of the message, throughput requirement of your messaging campaign, and the timeline when you want to start sending messages. Azure Communication Services enables you to send SMS using a variety of sender types - toll-free number (1-8XX), short codes (12345), and alphanumeric sender ID (CONTOSO). The following table walks you through the features of each number type:

Factors Toll-Free Short Code Alphanumeric Sender ID
Description Toll free numbers are telephone numbers with distinct three-digit codes that can be used for business to consumer communication without any charge to the consumer Short codes are 5-6 digit numbers used for business to consumer messaging such as alerts, notifications, and marketing Alphanumeric Sender IDs are displayed as a custom alphanumeric phrase like the company’s name (CONTOSO, MyCompany) on the recipient handset. Alphanumeric sender IDs can be used for a variety of use cases like one-time passcodes, marketing alerts, and flight status notifications.
Format +1 (8XX) XYZ PQRS 12345 CONTOSO*
SMS support Two-way SMS Two-way SMS One-way outbound SMS
Calling support Yes No No
Provisioning time 5-6 weeks 6-8 weeks Instant
Throughput 200 messages/min (can be increased upon request) 6000 messages/ min (can be increased upon request) 600 messages/ min (can be increased upon request)
Supported Destinations United States, Canada, Puerto Rico United States Germany, Netherlands, United Kingdom, Australia, France, Switzerland, Sweden, Italy, Spain, Denmark, Ireland, Portugal, Poland, Austria, Lithuania, Latvia, Estonia
Get started Get a toll-free number Get a short code Enable alphanumeric sender ID

* See Alphanumeric sender ID FAQ for detailed formatting requirements.

Next steps

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