The first step in setting up your transactional SMS messaging is to trigger an API call to pull back all of your short codes that are associated with your account. Be sure to have completed authenticating before moving to this next step. Follow the below steps to test this in Postman or a REST application of your choice.

1. Open https://api.listrak.com/sms in a tab.
2. Navigate to the shortcode tab.
3. Then Get SMS Short codes.
4. Copy the relative Get SMS Short codes URL from the right-hand side of the page.

5. Navigate to Postman.
6. Enter the base URL of https://api.listrak.com/sms.
7. Click Headers.
8. Enter your copied bearer token from the previous article.
9. Click Send.
10. Locate the Short Code ID.

You now have your SMS Short Code ID and can now call all your SMS lists.