Here’s how it works:

Until today, the Google Voice app had to make a request to the Google Voice server every time you wanted to make a call to send us the phone number you wanted to dial. Then the call would be connected via a Google Voice access number. With direct access numbers, we assign a unique phone number to every person you call. This means that we no longer need to use your data network to access the server each time you make a call, so calls will be placed much faster.