> ## Documentation Index
> Fetch the complete documentation index at: https://docs.klatt.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Inbound telephony

> Connect a Twilio number or custom SIP trunk to a Klatt workflow, then verify the call path before accepting real traffic.

Connect a Twilio number or custom SIP trunk to a Klatt workflow, then verify the call path before accepting real traffic.

## Prerequisites

* Access to the Klatt Console and **Telephony Configurations**.
* A saved workflow that is ready to answer an inbound call.
* Either a Twilio account with an approved number or the carrier details for a custom SIP trunk.

## Configure inbound calling

1. Open **Telephony Configurations** and choose **Add telephony configuration**.
2. Select **Twilio** or **SIP trunk**, enter the required configuration details, and save the configuration.
3. Import or add a phone number through the configuration’s phone-number controls.
4. Assign the inbound number to the workflow that should answer it.
5. Place a controlled test call and confirm the workflow, greeting, and end-call behavior.

## Constraints and failure states

Provider credentials and phone numbers are managed separately. An inbound number without an assigned workflow cannot route the intended call experience. Twilio callbacks or custom SIP carrier routing must be correct before live traffic is safe.

## Protect your data

Store provider credentials only in the protected configuration form. Restrict who can assign numbers and keep test callers and recordings synthetic.

## Related

* [Twilio](/integrations/telephony/twilio)
* [Custom SIP trunk](/integrations/telephony/custom-sip-trunk)


## Related topics

- [Custom SIP trunk setup](/integrations/telephony/custom-sip-trunk.md)
- [Twilio setup](/integrations/telephony/twilio.md)
- [API Trigger node](/voice-agent/api-trigger.md)
- [Call transfer tool](/voice-agent/tools/call-transfer.md)
- [AI Voice Agent Documentation and Workflow Guides](/index.md)