Can I force my phone to make calls using WiFi, even when wireless is available?

Question

When I was in the UK a couple years ago I could make calls back to USA using WiFi, because the wireless service was incompatible with my phone.
When I was in the Dominican Republic last year, even though I used GrooveIP and Google Voice, I came home to a $400+ wireless roaming bill, I think because the wireless service there IS compatible.  So how do I force my phone to make calls using WiFi, even when wireless is available?

Answer 1

    Hey there FredW,
A $400 bill would certainly cause my jaw to drop so I absolutely want to provide you steps to prevent this from happening going forward.
To avoid data charges you are going to want to make sure that Data roaming is turned off,http://vz.to/18oRFuS.
You'll also want to disable mobile data,http://vz.to/1hCPg4Q.
When using services such as GrooveIP, Google Voice, Skype you are going to want to make sure that you are connected to WiFi. Here is how to set up a WiFi connection,http://vz.to/II1jP6.
Let us know if you have any additional questions.
NicholasB_VZW
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