Originally Posted by
caburrito
You will be charged international rates for calls made by hangouts when outside of the US. So be sure to have some money inside your GV account if you plan on making calls. The rates can be reasonable, depending on the country.
Only for calls made to numbers outside the US and Canada. Calling back to US/CA is free*, as are all incoming calls. Also worth noting is that although you can call anywhere in the world for a price, you can't text outside US/CA at all.
*Google Voice's
official support page says "
*free from the U.S. & Canada
/ 1¢ from everywhere else", but this is either outdated or intended for an expansion of GV's dial-around service to other countries that never happened. VoIP calls made with Hangouts to American and Canadian numbers are definitely free, even when made from foreign cell or wifi networks.