Originally Answered: How Do Cingular Go Phones Work?
There are two main options for calls. In either case you purchase the prepaid amounts from a store, and depending on your usage, it gets deducted from your balance. Also, each time you buy prepaid amounts, there is an expiration time, by which you have to use it up, or you lose it.
In option 1, you get charged a flat rate of $0.25 for every minute (including partial minutes) or airtime that you use. Note that this is airtime, so incoming and outgoing calls cost the same. You can call any US number and receive incoming calls from anywhere in the world.
In this case, for example if you use the phone for 1 hour (60 minutes), your balance would decrease by $15 that day.
In option 2, you get charged a flat fee of $1 on every day that you use the phone (even if you use the phone for just one minute, and you don't get charged anything on days that you don't use the phone), and then, you are charged $0.10 for every minute of airtime. Again, you can call any US number and receive incoming calls from anywhere in the world.
Using the same example above, with this plan you would be charged $1 for using the phone, and then $6 for 60 minutes of usage, a total of $7.
So obviously, if you use the phone a lot, then the second option (with the $1 daily charge) works out cheaper.
The break-even point is 15 minutes of usage. If you use the phone for 15 minutes or more per day, then option 2 with the $1 daily charge is cheaper. If you use the phone for less than 15 minutes a day, then the other option is cheaper.