Try the following after you login to your att online account.
1. Cick on "wireless", and a bunch of other stuff you can click on it too, but just click the "wireless" till a page load up.
2. Once the page load up, you should see, "overview", "mobile #1", "mobile #2", etc....
3. Click on the phone number that you want to find out the contract end date.
4. You should be able to see a tab said "customer service summary", click on that.
5. Once you click on that, you will be able to see the contract start date and the end date on the first line.
Let me know if that helps.
If not, ill look into it.
