Google Voice has one of the lowest rates on international calls. To make calls, you use either the Google Voice website or the phone system, as long as you have one of your forwarding phones or smartphone available to complete the call.
In order to make international calls, you need to have credits in your Google Voice account. You can purchase credit through Google Wallet.
1. Log on to your Google Voice account
2. Click on the “+” sign next to “Credit” on the left side of your inbox or click on “Settings” then the “Billing” tab.
3. Click “Add Credit” under the “Billing” tab and the Google Wallet window will pop up.
4. Select to pay with a credit card on file or click the arrow and add a new payment method.
You will get a confirmation of your purchase sent to your email address you use to log in to Google Wallet. The maximum amount of credit you can have in your Google Voice account is $70.