Subscribe first to VoIP service and get a user account from your service provider. Receive then the SIP VoIP settings from your service provider to your device for example via an SMS message or as a sis package. Alternatively you can configure the VoIP settings manually by downloading and installing a separate SIP VoIP Settings tool from Forum Nokia:

http://www.forum.nokia.com/info/sw.nokia.com/id/d476061e-90ca-42e9-b3ea-1a852f3808ec/SIP_VoIP_Settings.html

After the VoIP settings have been provisioned, the VoIP service will appear in Contacts application. Select Menu > Contacts and scroll to the right to the VoIP service menu.

To activate the service, select Options > Log in when under the coverage of the VoIP network (e.g. your home WLAN network). Your device will then register to the SIP server. The VoIP service can be deactivated by selecting Options >Log out.

When the VoIP service is activated, the internet calls can be placed in the following ways:

  1. In Dialler by typing in the number and selecting Options > Call > Internet call. Alternatively, if VoIP service is defined as the default service, the internet call is automatically established when pressing the dial button.
  2. In Dialler by typing in the internet call (SIP) address by selecting Options > Open keyboard.
  3. In Contacts menu by opening the contact and selecting VoIP service as the call type.

To verify that the call is a VoIP call, check the icon in the telephony view. VoIP call is indicated by an icon with a handset and a globe.

Note that if using Nokia N97 device, you need phone software version 20.0.019 or later to be able to use VoIP. With Nokia N97 mini the VoIP support is available already starting from the first phone software version 10.0.020.