Twilio has special ability to turn toll-free phone numbers into high-throughput,numbers with high deliverability. The process for provisioning these numbers takes 3-5 business days and requires small additional expense. This service is most useful for high impact, large scale broadcasts.
Twilio process is to purchase the toll free numbers in your Twilio account, either in the Twilio console or via the Twilio integration in Prompt.io. You then email your Twilio account manager (or Prompt.io can go through our account manager, Jack Rice) with the numbers that you wish to upgrade. Twilio will require the name of the end customer (if digital agency), the content of the message, and the time frame of the send (date/time). Provisioning takes 3-5 business days.
Twilio charges $250 / month for the high throughput numbers.
Deliverability should increase substantially for whitelisted toll free numbers. For anything higher than 250k sends, this should be strongly considered best practice.
Organizations requiring high throughput toll free sends require special provisioning at Prompt.io. We typically ask for 48 hours notice, though in special cases 24 hours should be sufficient.
High throughput at 25mps will send approximately 90,000 messages an hour. Or, about 1m messages in the course of a 12 hour work day (7am - 7pm pacific). For higher capacity needs, multiple toll free numbers can be employed or the send should be split to multiple days.