Twilio and Telnyx are the two carriers most AI voice teams choose between. Both sell phone numbers, SMS, programmable voice, SIP trunking, and a WebSocket stream of raw call audio. Both work with Vapi, Retell, and LiveKit. The real differences are price, documentation depth, and network ownership.
All prices below are US pay-as-you-go list prices, checked on October 8, 2026, from each company's public pricing pages.
Price comparison
| Item | Twilio | Telnyx |
|---|---|---|
| US local number | $1.15/month | $1.00/month |
| US toll-free number | $2.15/month | $1.00/month |
| Inbound voice, local | $0.0085/min | about $0.0052/min |
| Outbound voice, local | $0.0140/min | about $0.007/min |
| WebSocket audio stream | $0.0044/min (Media Streams) | $0.0035/min (media streaming) |
| Managed speech relay | $0.07/min (ConversationRelay) | $0.05/min (Conversation Relay) |
| Call recording | $0.0025/min | $0.002/min |
| SIP trunk, inbound local | $0.0034/min | from $0.0032/min |
| SIP trunk, outbound US | $0.0100/min | from $0.005/min |
| SMS, US local, per segment | $0.0083 + carrier fee | $0.004 + carrier fee |
| 10DLC brand registration | $4.50 or $46 | $4.50 |
| 10DLC campaign vetting | $15 | $15 per review |
| 10DLC standard campaign | $10/month | $10/month |
Telnyx voice is two fees: a $0.002 per minute Call Control fee plus the SIP rate. The table shows the sum. Carrier SMS surcharges (for example $0.0035 to $0.005 per outbound message) are passed through by both.
Sources: Twilio voice, Twilio SMS, Twilio SIP trunking, Twilio 10DLC fees, Telnyx Call Control, Telnyx SIP, Telnyx messaging, Telnyx 10DLC fees.
What 10,000 voice minutes cost
For an inbound AI voice agent that streams audio to your own server:
| Twilio | Telnyx | |
|---|---|---|
| 10,000 inbound minutes | $85 | about $52 |
| 10,000 minutes of audio stream | $44 | $35 |
| 1 local number | $1.15 | $1.00 |
| Total telecom | about $130 | about $88 |
Your speech-to-text, LLM, and text-to-speech costs come on top. They are usually larger than the telecom bill, so the carrier difference matters most at high volume.
Raw audio for your own voice pipeline
Both carriers can stream call audio to your WebSocket server and accept audio back.
- Twilio Media Streams supports one-way and two-way streams. Two-way streams let your app play generated speech into the call. It is the most widely documented option, and many open-source voice agent examples use it.
- Telnyx media streaming is also bidirectional and supports more codecs: PCMU, PCMA, G722, OPUS, AMR-WB, and L16. Wideband codecs matter when the call leg itself is wideband, such as a SIP or WebRTC call. Most calls from mobile phones reach you as 8 kHz audio either way.
If you do not want to handle audio, both sell a relay product that does speech-to-text and text-to-speech for you and sends your server text: Twilio ConversationRelay at $0.07 per minute and Telnyx Conversation Relay at $0.05 per minute.
SIP and voice platforms
If your agent runs on Vapi, Retell, or LiveKit, the carrier mainly supplies the number and the SIP leg.
- Vapi imports numbers from both Twilio and Telnyx. See Vapi phone numbers: free vs Twilio vs Telnyx.
- Retell connects to both through SIP trunking. See connect a phone number to Retell.
- LiveKit documents SIP trunks from both carriers for LiveKit Agents.
Network and support
Telnyx says it owns its network and holds its own telecom licenses, with a private backbone between its points of presence. That is Telnyx's own claim. Twilio has the larger ecosystem: more SDKs, more tutorials, more answers on forums, and more voice-platform defaults built around it.
SMS for agents
Both require A2P 10DLC registration for business texts from US local numbers, and both pass through the registry fees. Telnyx's base SMS price is about half of Twilio's. For a conversational agent, the carrier surcharges and 10DLC fees are often a large share of the bill on both. See the A2P 10DLC guide for AI agents.
Which to choose
- Choose Telnyx if cost per minute matters, you stream raw audio, or you want wideband codecs.
- Choose Twilio if you want the most examples and integrations, or your team already uses it.
- Use both if you need failover. Many platforms keep a second carrier for outages and number availability.
Numbers for Agents is building a number API designed for agents, with SMS, signed webhooks, SIP, and raw WebSocket audio. It is in private beta. Join the waitlist below if you want to compare it when it opens.
FAQ
Is Telnyx cheaper than Twilio?
Yes, at list price, on numbers, voice, media streaming, and SMS. For example, US local outbound voice is about $0.007 per minute on Telnyx and $0.014 on Twilio. Volume discounts can change the gap.
Do Twilio and Telnyx both work with Vapi?
Yes. Vapi's dashboard and API import numbers from Twilio and from Telnyx. You can also connect either carrier to Vapi over SIP.
Which is better for low latency voice AI?
Both stream audio over WebSockets. Latency depends more on where your servers run and on your speech and LLM models than on the carrier. Place your media server close to the carrier's media region and test with real calls.
Can I move my numbers from Twilio to Telnyx?
Yes, by porting. US and Canada ports are usually self-service and take days. You also need to repoint webhooks and move your 10DLC campaign.
Get a phone number for your agent
Numbers for Agents is an API for agent phone lines: numbers, SMS, call webhooks, SIP, and WebSocket media. It is in private beta. Join the waitlist for early access and pricing.