Check your at&t bill. I had noticed an item on my bill, “SMS Intl $0.25 Msg Out”. Initially I thought that I had somehow sent an international SMS message. And it cost $0.25, which is much more than $0.00 for the first 100 domestic SMS messages in my “package”.
Next month my bill included this item too. Since I mostly send text messages to Twitter, I thought that the Twitter short code may be causing the charge. (Because how does Twitter make money, by the way?) So I stopped sending SMS to Twitter.
So this time, on my December 2007 bill, I again noticed the “SMS Intl $0.25 Msg Out” charge and called customer service. I asked the agent if they could tell me what SMS messages were “international” since they weren’t marked on my call detail. She said that she would take a look. Moments later, she returned and said that these charges were due to a billing problem. The billing problem was incorrectly marking domestic SMS messages as international. She said that they announced this billing issue a couple of months ago and were performing automated updates to fix the problems, but it was difficult and they didn’t get all of the charges reversed. She was able to credit my account for all of the charges from the past three months that were incorrectly marked as international SMS. She also made the off hand remark that I didn’t use SMS very much. I said that that was because they started getting charged $0.25 per message so I cut back. She said that that was a good point. 🙂
So double check your at&t bill.