Connect a SIP Trunk

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

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Rounded SIP origination URI

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

sip:sip.callrounded.com;transport=tcp

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Configuration methods

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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.

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Method 2: Custom configuration

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

📧 team@callrounded.com

Our team will support you with:

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

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Configuration in Rounded

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1. Phone number settings

• Phone number: Your number in international format (e.g.: +33156273645)
• Friendly name: A descriptive name to easily identify this number

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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

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Call flows

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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

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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

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SIP Trunk advantages

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

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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