技术咨询：Twilio是否支持无振铃语音信箱（呼叫直转语音信箱）功能

Hey there! Let's tackle your two Twilio voicemail questions head-on:

1. 无振铃语音信箱（Ringless Voicemail）支持情况 #

Yes, Twilio does support ringless voicemail through its Ringless Voicemail Drop feature. This lets you send a pre-recorded voicemail directly to a recipient's voicemail box without their phone ringing at all.

To implement this, you’ll use Twilio’s Voice API. When creating a call request, configure it to detect the recipient’s voicemail system immediately. Set parameters like AnsweredBy to machine and point the call to a TwiML bin or webhook that plays your pre-recorded message once the voicemail picks up. Since this skips the ringing phase entirely, it’s exactly the ringless voicemail you’re looking for.

2. 呼叫直接转语音信箱功能 #

Twilio absolutely provides tools to route calls directly to voicemail, whether you’re handling incoming calls or initiating outgoing ones. Here’s how to set this up for both scenarios:

• Incoming Calls: For calls coming into your Twilio number, use TwiML or Twilio Studio to build a flow that sends callers straight to voicemail. A simple TwiML example would look like this—this response skips any ringing for your side and immediately prompts the caller to leave a message:

<Response>
  <Say>Please leave your message after the beep.</Say>
  <Record maxLength="300" />
</Response>

You can also integrate Twilio’s built-in voicemail features if you want more robust handling, like sending transcriptions or notifications when a message is left.

• Outgoing Calls: If you’re initiating a call that you want to send directly to voicemail, use the Voice API’s Create Call endpoint with machine detection enabled. Set MachineDetection to Enable and a short MachineDetectionTimeout to trigger the voicemail flow as soon as the system is detected. This ensures the call routes to voicemail without ringing the recipient’s phone first.

I totally get it if you didn’t spot this right away in the official docs—sometimes these use cases are spread across API references and guides rather than being in a single dedicated section. The core is leveraging Twilio’s call control and machine detection capabilities to build these flows.

内容的提问来源于stack exchange，提问作者Don