Number Masking - Try it without code



To add this product to your account, contact a Telesign expert. This product is available for full-service accounts only.

Use this action to create an anonymous session for SMS communication with number masking. If this service is enabled, you can try a test request in the API Explorer on the POST /v1/anonymous/session/sms reference page. You can also get a code snippet for the request.

Before you begin

Ensure that you have the following:

  • Authentication credentials: Your Customer ID and API Key. If you need help finding these items, go to the support article How do I find my Customer ID and API Key.
  • SMS capable phone numbers from Telesign: You will need SMS capable-only (not voice capable-only or dual-capable) numbers from Telesign as masking IDs when using this action. Contact our Customer Support Team for assistance.




Using your account credentials in the API Explorer to make a request results in your account being charged for the transaction.

You are subject to all compliance rules as appropriate for your transaction.

  1. Open the reference page for the POST /v1/anonymous/session/sms endpoint.
  2. Under the AUTHENTICATION header in the right panel of the page, put your Customer ID in the Customer ID field and your API key in the API Key field.
  3. Go to the BODY PARAMS section in the middle panel of the page. For phone_number_1, enter the complete phone number with the country code for one of your two test phone numbers. Do not include any special characters or spaces.
  4. For phone_number_2, enter a second complete test phone number. Do not include any special characters or spaces.
  5. For validity_period, enter an integer between 1 and 720 (assuming the units are configured to hours for your account). This is the time duration that you want the session to last. The units may vary depending on your configuration at setup, ask our Customer Support Team if you are not sure what units apply for your account. (See full parameter details on the API reference page at POST /v1/anonymous/session/sms).
  6. Select Try It! in the right panel to send your request to Telesign. You will be charged the standard rate for this transaction.
  7. You can also select the copy icon to the left of Try It! to copy the code snippet displayed. To change the programming language of the snippet, select one of the options under the LANGUAGE header in the right sidebar.
  8. After you send your request, look through the response and make a note of the masked_id and session_id values. The masking ID (masked_id) for each number is what your users will use to communicate with their real numbers masked. You will use the session ID to track the users' session and monitor as needed.