Since Google Voice numbers aren't listed in phone books or connected to physical addresses, they're difficult to trace. When you call contacts from your Google Voice number, it shows up on their caller ID, but standard phone traces don't reveal your identity. If law enforcement agencies become involved, Google provides them with your account information, including the IP address from which you created the account and placed calls.

Google Voice Number

Unlike some Voice over IP services, Google Voice assigns a phone number to your account and displays this number on the recipient's caller ID when you make a call. If you call other Google Voice users, your name, number, email address and profile picture appear in their inbox. Therefore, they can return your call or block you from making further calls by clicking the “More” menu below your name and selecting the appropriate option.

Tracing Google Voice Calls

If your recipient enters your Google Voice number in an online directory, such as White Pages, Switchboard or AnyWho, the search returns the Bandwidth headquarters, the company that issues VoIP numbers to Google Voice users. Since Bandwidth has many headquarters across the country, your Google Voice area code determines which building the search finds on a map. Finding your location and identity from this information is impossible, especially since you can choose any area code for your Google Voice number.

Google's Privacy Policy

The only personnel with the information needed to find you based on your Google Voice number are a few trusted Google employees. According to Google's privacy statement, your information is encrypted with Secure Socket Layer protection and restricted to employees and outside personnel contractually obligated to respect your privacy. You agree to these terms when you create a Google account, and while these employees can be fired for tampering with your data, they have the necessary level of access, albeit to millions of other accounts as well.

Law Enforcement Involvement

A government agency can request your data from Google by providing a subpoena, court order or search warrant. However, Google claims to take users' privacy very seriously and doesn't give information to authorities unless the request passes a rigorous internal process. If authorities have requested your data from Google, you receive an email notifying you of the request. If Google finds a subpoena, court order or search warrant valid, it provides the government agency with specific account information, including your IP address, which can reveal your physical location.