In most cases, if you make a mistake while Telefiling, you can usually correct it very easily over the phone. However, in some cases, you would be required to file an amended return.
After you enter each item from your return, Telefile will speak back your entry. Verify that the amount spoken, is the correct amount. If it is the correct entry, telefile will ask you to press 1 to confirm. If it was not the correct amount, then press 2 to reenter the amount.
If you realize that you made a mistake after confirming an item but before entering your PIN signature in Item 18, you may hang up and start again. Everything that you entered will be erased. You may call back and start with item one again.
Please note, that when you enter your “pin” signature in item eighteen, the return is considered filed. At that point, if you realize that you entered incorrect information, you must correct the mistake by filing Form CT-1040X, the Amended Income Tax Return For Individuals, with the Department.