If you have to choose between the two carriers, Telnyx is the better option for Voice AI Agents.
Telnyx is consistently cheaper, often roughly half the cost or better for voice minutes, especially at scale for AI agents.
Telnyx: ~$0.002–$0.007 per minute (inbound/outbound, often with SIP trunking fees included in effective rates). Programmable Voice and SIP options keep it low.
Twilio: ~$0.0085–$0.014 per minute for US local calls (inbound/outbound). Higher for toll-free or certain routes.
Example at volume (e.g., 100k outbound minutes/month):