### Answer Yes, you can add toll-free numbers in Retell AI. There are two main options: 1. Purchase directly from Retell You can buy US toll-free numbers through Retell for $5/month. [(1) ]() When creating a phone number via API, set

toll_free

to `true`: [(2) ]()

javascript
const phoneNumberResponse = await client.phoneNumber.create({
  toll_free: true
}) ;

Toll-free numbers cost $0.06 per minute for inbound calls, while outbound calls are charged at the same rate as regular U.S. numbers. [(1) ]() *2. Import via SIP trunk (Twilio, Telnyx, etc.) * You can also connect an existing toll-free number from providers like Twilio through elastic SIP trunking. [(3) ]() Important note for inbound calls on imported toll-free numbers: Set the origination SIP URI to: [(4) ]()

sip:5t4n6j0wnrl.sip.livekit.cloud;transport=tcp

UDP transport doesn't work for toll-free inbound—switching to TCP resolves it.

​ To learn more, see the sources I considered: [[1] Purchase phone number](https://docs.retellai.com/deploy/purchase-number) [[2] Create Phone Number](https://docs.retellai.com/api-references/create-phone-number) [[3] I’m trying to use a toll-free number (connected from Twilio through a SIP trunk)](https://retell.discourse.group/t/i-m-trying-to-use-a-toll-free-number-connected-from-twilio-through-a-sip-trunk/127) [[4] toll free numbers?](https://discord.com/channels/1186424376300679209/1281625260948590653) ​

Feel free to tag @AI Evy with additional questions. I also appreciate feedback, it helps me improve.