In my VAPI assistant, the latency is around 0.7 second (≈700 ms). However, when I test it on a live call through Twilio, the latency increases to 4 seconds. Why does this happen, and how can it be addressed? https://cdn.discordapp.com/attachments/1412812183573762099/1412812184408293416/image.png?ex=68b9a761&is=68b855e1&hm=ff6707cbd677a56958e41424e8eed01de49e9d433dcd6008720293bf7a4c5970&

Suggestion: Twilio conferencing and call bridging can introduce significant latency. To reduce this, try minimizing the use of conference rooms or on-hold steps in your call flow. For example, directly connect the user to the Vapi assistant without intermediate Twilio conference logic:

js
// Directly update the inbound call to fetch Vapi TwiML
await client.calls(callSid).update({
  url: 'https://your-server/vapi-twiml-endpoint',
  method: 'POST'
});

Review your call flow to ensure the user is not unnecessarily placed on hold or in a conference, as this can help bring latency closer to Vapi's native ~800 ms. [See more in the Vapi+Twilio call handling guide.](https://docs.vapi.ai/calls/call-handling-with-vapi-and-twilio) Sources: - [Call Handling with Vapi and Twilio](https://docs.vapi.ai/calls/call-handling-with-vapi-and-twilio) - [FAQ: Latency](https://docs.vapi.ai/faq)

@User @User Any Solution ?

Getting the exact same issue

Yes switching provider might be a solution

Have you tried Telnyx?

@Pedro Lourenco No, but have you given it a try?

Hey! To help track down this issue, could you share: \- The call ID \- When exactly this happened (the timestamp) \- What response you expected to get \- What response you actually got instead This would really help us figure out what went wrong!

Call ID: 2d6f72da-c4e2-496f-97dc-56cdbe8c326f When this happened: It’s not a one-time issue — it happens on every call I make. I’ve already tested this across dozens of calls. Expected behavior: I expect the conversation to flow naturally with low latency, similar to how it performs on VAPI (around 800ms). Actual behavior: On Twilio, the assistant’s responses are delayed by about 3–4 seconds, which makes the conversation feel unnatural and laggy. Impact: The high latency creates a poor user experience and breaks the natural back-and-forth flow of the conversation Thanks.

Please adjust your endpointing settings:

"transcriptionEndpointingPlan": {
     "onPunctuationSeconds": 0.1,
     "onNoPunctuationSeconds": 0.8,  // Reduce from 1.5s
     "onNumberSeconds": 0.3          // Reduce from 0.5s
   }

Also consider eleven_turbo_v2_5 instead of eleven_flash_v2_5 for lower latency on the voice config.

Thanks Kyle I will update and share the feedback with you soon.

It won't be reduced much since VAPI servers are located in US. International calls will always result in higher latency with VAPI until we get more server locations

Ok Thanks

why exactly would turbo v2.5 have lower latency than flash v2.5?

Flash Has the Lower Latency

i know, i asked bc kyle said to use turbo rather than flash for lower latency - i assume this was a mistake, but want to check

Yes, that was a mistake on my part. I realize that flash is slightly faster than turbo

Would self-hosting in a region close to me through AWS lead to a significant improvement?

Yes, but currently our team is reworking the on-prem deployment and has a rough ETA of end of q4