Can I send or receive text messages with a Twilio toll-free phone number?
Yes. Toll-free phone numbers in the US and Canada are enabled to send and receive text messages domestically within the two countries. To receive text messages on your toll-free phone number, you will need to configure your SMS request URL.
Toll-free phone numbers in the United Kingdom are not able to send or receive text messages.
When making an SMS app with Twilio, you must use an SMS enabled phone number. Please refer to this list of SMS enabled phone numbers.