The Base plan includes 100 free SMS per month. Users on the base plan will be blocked once you hit the limit of 100 free sms per month. If you are on a paid subscription, it includes 100 free SMS per month. After your first 100 SMS logins, a market rate surcharge will be applied to each SMS sent. Please
refer to this document to see the surcharges based on region. To enable SMS login, you will be required to provide your payment details and you will be billed at the end of each month based on usage.