Can I add the SMS capability to my toll-free phone number without porting it into Twilio?
Twilio can add SMS capabilities to your existing toll-free phone number without porting your phone number into Twilio. The SMS messaging on the toll-free number would work with Twilio’s API while the Voice portion would continue to run on your existing phone system. This feature is, however, currently in beta.
If you are interested in this feature, you can sign up for the beta here.