attSay I'm on a plan with AT&T that charges me 40 cents/minute for voice calling.
If I talk for 0 seconds (which has happened - I call, get the machine and hang up), am I charged 40 cents?
If I call for exactly 1 minute (1:00), am I charged 40 or 80 cents? What about 1:01?
Even if you only use 1 second, you'll get charged the full minute. I can't verify it, and not knowing your exact terms won't help, but even if you don't leave a message, it is still airtime you are using, particularly since the cell phone doesn't necessarily know that it is an answering machine picking up the line vs a human.
Airtime and other measured usage are billed in full-minute increments, and actual airtime and usage are rounded up to the next full increment at the end of each call for billing purposes. AT&T charges a full-minute increment of usage for every fraction of the last minute used on each wireless call.
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