1. Open the phone and press the green call button to open the phone dialer.
2. Press the Menu key (top left key on the keypad, looks like 3 lines stacked on top of each other)
3. Scroll down and select Call settings.
4. Click on Calls.
5. Scroll down and select Call forwarding.
6. Click on Voice.
7. Select Always forward and input the number you’d like the calls to go to.
8. To disable, follow steps 1-7 but then click on disable on step 7 to stop the forwarding.

If you need any further assistance with this question, please contact the Sonim Customer Experience Center at 1-833-MY-SONIM (1-833-697-6646) or email us at [email protected].  We are open 24 hours a day, Monday-Friday and we will further assist in troubleshooting.