Connect a SIP Trunk

Configure your own phone number via SIP trunking for inbound and outbound calls

SIP trunking allows you to connect your own phone number to Rounded to receive and make calls. This solution is ideal for:

• Using your existing numbers
• Benefiting from preferential rates from your operator
• Keeping control over your telephony infrastructure

Rounded SIP origination URI

To configure your SIP trunk, you will need to use this origination URI:

sip:sip.callrounded.com;transport=tcp

Configuration methods

Method 1: Elastic SIP Trunk (Recommended)

This method uses standard SIP trunk services from major providers. It’s simple to configure and compatible with most operators.

Documented providers:

• Twilio
• Telnyx
• Zadarma

Other providers: Any standard SIP trunk provider will work with Rounded. The above are just our documented examples.

Method 2: Custom configuration

For specific needs or advanced configurations, contact our technical team:

📧 [e-mail]

Our team will support you with:

• Custom SIP configurations
• Integrations with existing PBX systems
• Multi-tenant configurations
• Dedicated technical support

Configuration in Rounded

1. Phone number settings

• Phone number: Your number in international format (e.g.: [phone])
• Friendly name: A descriptive name to easily identify this number

2. SIP Trunk settings

• Termination URI: Your provider’s SIP address (e.g.: sip.myprovider.com)
• Username: Optional, provided by your SIP operator
• Password: Optional, provided by your SIP operator

Call flows

Outbound calls

When your Rounded agent makes a call:

1. Rounded routes the call to your termination URI
2. Your SIP provider routes the call to the recipient
3. The caller ID displayed is the one configured

Inbound calls

When someone calls your number:

1. Your SIP provider receives the call
2. It transfers it to the Rounded URI: sip:sip.callrounded.com;transport=tcp
3. Rounded triggers your voice agent

SIP Trunk advantages

Reduced costs: Use your negotiated rates
Flexibility: Keep your existing numbers
Scalability: Easily add new numbers
Reliability: Redundancy and high availability

Next steps

1. Choose your SIP provider - use our documented guides (Twilio, Telnyx, Zadarma) or any other SIP provider
2. Configure your SIP trunk according to the provider’s guide
3. Test the configuration with a test call
4. Deploy your voice agents

Using a different provider? No problem! Any standard SIP trunk will work - just use the Rounded origination URI: sip:sip.callrounded.com;transport=tcp

💡 Tip: Start with a test number before migrating your production numbers.