My goal was to move my old number to Google Voice, and replace my main number with a new one that I’d pick out myself. The whole process cost me only $23—but it was a bit trickier than it sounds.

A Letter of Authorization (LOA) is a document that you must send to your telecom provider when you want to switch to a new business phone service but keep your old phone number. It lets both your ...

When you get a new phone number, mobile carriers will often “recycle” your old one—assigning it to a new phone and, therefore, a new customer.