Add a Phone Number

Connect phone numbers to your AI voice agents for inbound and outbound calls

Overview

To enable your AI voice agents to make and receive phone calls, you need to connect a phone number. urvo supports two methods for adding phone numbers:

Twilio Integration: Import existing Twilio phone numbers for quick setup with full inbound and outbound support. Easy setup with Twilio credentials, verified caller IDs for outbound-only.
SIP Trunking: Connect your existing telephony infrastructure directly via SIP protocol. Use existing phone systems with TLS encryption support and custom SIP headers.

Option 1: Twilio Integration

Connect a Twilio phone number to your agent to handle both inbound and outbound calls.

Phone Number Types & Capabilities

urvo supports two types of Twilio phone numbers with different capabilities:

Type	Inbound Calls	Outbound Calls	Use Case
Purchased Twilio Numbers	✓ Supported	✓ Supported	Full phone system with AI agents
Verified Caller IDs	✗ Not supported	✓ Supported	Use your existing business number for outbound AI calls

Note: During phone number import, urvo automatically detects the capabilities of your number based on its configuration in Twilio.

Prerequisites

A Twilio account
Either:
- A purchased & provisioned Twilio phone number (for inbound + outbound)
- OR a verified caller ID in Twilio (for outbound only)

Step 1: Import a Twilio Phone Number

In your urvo dashboard, go to the Phone Numbers tab.
Click "Import Phone Number" and select Twilio.
Fill in the following details:
- Label: A descriptive name (e.g., "Customer Support Line")
- Phone Number: The Twilio number you want to use
- Twilio SID: Your Twilio Account SID
- Twilio Token: Your Twilio Auth Token

Where to find your credentials: You can find your Account SID and Auth Token in the Twilio admin console.

Applied Settings

urvo automatically configures the Twilio phone number with the correct settings and detects whether your number supports:

Inbound + Outbound: Numbers purchased through Twilio
Outbound Only: Numbers verified as caller IDs in Twilio

Step 2: Assign Your Agent (Inbound-capable numbers only)

If your phone number supports inbound calls, you can assign an agent to handle incoming calls:

Select the phone number from your Phone Numbers list.
Click the "Assign Agent" dropdown.
Select the agent you want to handle inbound calls.

Note: Numbers that only support outbound calls (verified caller IDs) cannot be assigned to agents and will show as disabled in the agent dropdown.

Test the agent by giving the phone number a call. Your agent is now ready to handle inbound calls and engage with your customers. Monitor your first few calls in the Calls History dashboard to ensure everything is working as expected.

Option 2: SIP Trunking

SIP (Session Initiation Protocol) trunking allows you to connect your existing telephony infrastructure directly to urvo. This integration enables you to use your existing phone systems while leveraging urvo's advanced voice AI capabilities.

Benefits of SIP Trunking

Connect your Private Branch Exchange (PBX) or SIP-enabled phone system
Route calls to AI agents without changing your existing phone infrastructure
Handle both inbound and outbound calls
Leverage encrypted TLS transport and media encryption for enhanced security

Requirements

A SIP-compatible PBX or telephony system
Phone numbers that you want to connect to urvo
Administrator access to your SIP trunk configuration
Appropriate firewall settings to allow SIP traffic
Audio codec compatibility: Your system must support G711 or G722 audio codecs

TLS Support: For enhanced security, ensure your SIP trunk provider supports TLS transport.

Step 1: Navigate to Phone Numbers

Go to the Phone Numbers section in your urvo dashboard.

Step 2: Import SIP Trunk

Click on "Import a phone number from SIP trunk" button to open the configuration dialog.

Step 3: Enter Basic Configuration

Complete the basic configuration with the following information:

Label: A descriptive name for the phone number
Phone Number: The E.164 formatted phone number (e.g., +15551234567)

Step 4: Configure Transport and Encryption

Configure the transport protocol and media encryption settings:

Transport Type

TCP: Standard TCP transport
TLS: Encrypted TLS transport for enhanced security

Media Encryption

Disabled: No media encryption
Allowed: Permits encrypted media streams
Required: Enforces encrypted media streams

Security Best Practice: Use TLS transport with "Required" media encryption for maximum security. This ensures both signaling and media are encrypted end-to-end.

Step 5: Configure Outbound Settings

Configure where urvo should send calls for your phone number:

Address: Hostname or IP address where the SIP INVITE is sent (e.g., sip.telnyx.com). Enter only the hostname or IP address, not a full SIP URI.
Transport Type: Select TCP or TLS
Media Encryption: Configure encryption for RTP media streams

Step 6: Add Custom Headers (Optional)

If your SIP trunk provider requires specific headers for call routing or identification:

Click "Add Header" to add custom SIP headers.
Enter the header name and value as required by your provider.
You can add multiple headers as needed.

Custom headers can be used for:

Call routing and identification
Billing and tracking purposes
Provider-specific requirements

Step 7: Configure Authentication (Optional)

Provide digest authentication credentials if required by your SIP trunk provider:

SIP Trunk Username: Username for SIP digest authentication
SIP Trunk Password: Password for SIP digest authentication

Authentication Methods: Digest authentication uses username/password credentials (recommended). ACL authentication uses IP address allowlisting for access control. If left empty, ACL authentication will be used, which requires you to allowlist urvo IP addresses in your provider's settings.

Step 8: Complete Setup

Click "Import" to finalize the configuration.

Making Calls to urvo SIP Trunk

When initiating calls to urvo, use the proper SIP URI format:

sip:+19991234567@sip.rtc.elevenlabs.io:5060

Where:

+19991234567 is the identifier (typically a phone number in E.164 format)
The identifier can also be any string value, such as 1000 or john

Common Mistake: Do not initiate calls directly to sip@sip.rtc.elevenlabs.io:5060 without an identifier. The SIP URI must include a phone number or identifier after the sip: prefix and before the @ symbol.

Assigning Agents to Phone Numbers

After importing your phone number (via Twilio or SIP trunk), you can assign it to an agent:

Go to the Phone Numbers section in your dashboard.
Select your imported phone number.
Click "Assign Agent".
Select the agent you want to handle calls to this number.

Troubleshooting

Connection Issues

Verify your firewall settings allow SIP traffic
Ensure the SIP trunk address is correct
Check that authentication credentials are valid

No Audio or One-Way Audio

Verify your system supports G711 or G722 audio codecs
Check media encryption settings match between systems
Ensure RTP ports are open in your firewall

TLS and Encryption Issues

Ensure your SIP trunk provider supports TLS 1.2 or higher
Verify SRTP compatibility if requiring media encryption

Frequently Asked Questions

Can I use my existing phone numbers with urvo?

Yes! You can import existing Twilio numbers or connect your existing phone system via SIP trunking.

What SIP trunk providers are compatible?

urvo is compatible with most standard SIP trunk providers that support TCP or TLS transport and G711/G722 audio codecs.

Should I use TLS transport?

Yes, TLS transport is recommended for enhanced security. It encrypts the SIP signaling to protect your call data.

How many concurrent calls are supported?

Support for multiple concurrent calls depends on your subscription tier. Contact support for specific limits.

Do I need to match the leading + format when importing phone numbers?

Yes, phone numbers should be in E.164 format (e.g., +15551234567) for proper routing.

Next Steps

With your phone number configured, you're ready to: