# How to receive a call You can forward incoming calls on any number of your choice via our [Flow Builder](https://dashboard.messagebird.com/en/flow-builder/) or through the API. **Flow builder** When you have purchased a Voice-enabled virtual mobile number, you can easily forward all incoming calls to another phone number or SIP URI by using our [Flow Builder](https://dashboard.messagebird.com/en/flow-builder). Check [How to forward calls to another phone number or SIP URI](https://docs.bird.com/connectivity-platform/how-to-guides/how-to-forward-calls-to-another-phone-number-or-sip-uri) for a step by step guide on how to set this specific flow. **Forwarding to SIP (SIP URI formatting)** When forwarding the incoming calls to a SIP trunk, please use the format below to insert your SIP URI: "sip:\@\"\ for example: *sip:*[*+31612345678@sip.domain.com*](mailto:+31612345678@sip.domain.com) **Signalling IP's** You may whitelist below signalling IP's when receiving calls on your own SIP URI: * Asia: 35.186.152.240 * Europe: 104.199.82.179 * US: 104.196.15.81 Media IPs: \- 104.199.61.220 \- 104.199.69.60 \- 104.196.222.116 \- 35.185.41.80 \- 35.186.148.117 \- 35.186.147.231 **Voice codecs:** MessageBird supports the following codecs: * PCMA (G711a) * PCMU (G711u)