Sending SMS messages using Azure Communication Service

Kris Hahn 20 Reputation points
2026-05-27T14:54:04.8833333+00:00

I have created an Azure Communication Service and I got a toll free phone number, but to be able to use that I need to do a submission to activate the SMS option.

At this point I'm in the development of my system and working out the details and workflow for using the SMS option and I'm looking to see how I get it configured so I can use it for sending test messages to my personal phone during the development testing phase. The next step will be to get it set up so I can do some UAT testing.

Any help guiding me in the correct direction would be greatly appreciated.

Azure Communication Services

1 answer

Sort by: Oldest
  1. AI answer

    2026-05-27T14:54:24.53+00:00

    To send test SMS messages from Azure Communication Services (ACS) to a personal phone using a toll-free number, two main pieces must be in place:

    1. Toll-free number verification/activation for SMS
      For new toll-free numbers, SMS verification is mandatory for sending SMS traffic to US and Canada. Until the number is fully verified, SMS traffic to US/CA is blocked. Use the toll-free verification process described in the SMS quickstarts:
      • Follow the guidance in Quickstart for submitting a toll-free verification (linked from the SMS quickstarts as “Quickstart for submitting a toll-free verification”).
      • Only fully verified toll-free numbers are authorized to send SMS traffic; any SMS traffic from unverified toll-free numbers to US and CA phone numbers is blocked.
      Relevant notes from the docs:
      • “To use a new toll-free number for sending SMS messages, you must complete a toll-free verification process.”
      • “Only fully verified toll-free numbers are authorized to send out SMS traffic. Any SMS traffic from unverified toll-free numbers directed to US and CA phone numbers are blocked.”
      While the detailed portal steps are not in the provided context, another tutorial notes that verification is done from the ACS resource under Telephony and SMS → Regulatory Documents, where the required validation documentation is added.
    2. Configure sending SMS from ACS for dev/test
      Once the toll-free number is verified, configure a simple sender to test to a personal phone: Option A – Use a Logic App / Power Platform flow
      1. Create a workflow (Logic App or Power Automate flow).
      2. Add the Send SMS (or SMS) action/connector.
      3. Configure the connector with:
        • The ACS connection string for the resource.
        • From: the verified ACS toll-free number.
        • To: the personal mobile number for testing.
        • Message content: e.g., “Hello from Logic Apps!”
      4. Save the workflow and run it manually to send a test SMS.
        The quickstart describes: specify source and destination phone numbers and message content, then select Save and Run to test.
      Option B – Use an SDK (Java, .NET, JavaScript, Python)
      1. Ensure prerequisites for the chosen language (SDK, runtime, ACS resource, SMS-enabled number) are in place.
      2. Use the corresponding “Send an SMS message” quickstart for that language to configure:
        • ACS connection string.
        • From: ACS toll-free number.
        • To: personal mobile number.
        • Message text.
      3. Build and run the sample as described (for example, with Java: mvn compile, mvn package, then mvn exec:java ...).
    3. Troubleshooting delivery during dev/UAT
      If messages do not arrive:
      • Confirm the toll-free number is fully verified; unverified numbers will be blocked for US/CA.
      • Enable delivery reporting with Event Grid to capture delivery details, as described in the SMS quickstarts under troubleshooting.
    4. Scaling from dev to UAT
      After basic dev testing to a personal phone works:
      • Reuse the same ACS resource and toll-free number.
      • Point the “To” numbers at UAT test users’ phones.
      • Optionally, add workflow logic (e.g., via Logic Apps/Power Automate) to integrate SMS into the application’s UAT flows.

    References:

    AI-generated content may be incorrect. Read our transparency notes for more information.

    Was this answer helpful?

Your answer

Answers can be marked as 'Accepted' by the question author and 'Recommended' by moderators, which helps users know the answer solved the author's problem.