Amending a Connecticut Income Tax Return
If corrections are necessary, you must file Form CT-1040X, Amended Connecticut Income Tax Return. Do not submit a second Form CT-1040 or Form CT-1040NR/PY.
ON-LINE - Amend your return using the TSC-IND, our free, online filing system. Login to your account, select the CT-1040X filing option and choose the period you wish to amend. On-line amendments can only be filed after the original return has processed.
PAPER - If you cannot use the TSC-IND, download the amended return from our website, complete it, and then mail it to DRS.
NOTE: Amended returns do not have the option to choose direct deposit.
If you received or are expecting a refund and now you owe more money with the amended return
If you have not deposited the check, return it to the Department as soon as possible (with "VOID" written across the check) along with a letter explaining that an amended return will be filed that will reduce the refund. DRS will redeposit the money and credit it to your account and will be applied against the balance due when you file the amended return. The check and letter should be mailed to:
Department of Revenue Services
Attn:Accounts Receivable Unit
25 Sigourney Street, Ste. 2
Hartford, CT 06106
If the check was already deposited to your account, you will have to write a check for the full amount due when you file the amended return. Any additional balance due with the amended return will be subject to interest at the rate of 1% per month or fraction of a month.
When must an amendment be filed in order to claim a refund?
In general, you must amend a previously-filed Connecticut income tax return to claim a refund of taxes within 3 years of the original due date or, if you filed a timely request for extension of time to file your Connecticut income tax return, within 3 years of the earlier of the date you filed the return or the extended due date.
You must amend your previously-filed Connecticut return even if the following occurs more than 3 years after the due date or extended due date of the original return. However, you may have longer than 3 years to amend under the following circumstances:
If you amend your federal income tax return or if your income is changed or corrected by the Internal Revenue Service and the change affects your Connecticut income tax liability (including your alternative minimum tax liability), you must file Form CT-1040X within 90-days of the change or amendment of your federal return. If you file Form CT-1040X no later than 90 days after the final determination, any Connecticut income tax overpayment resulting from the final determination will be refunded or credited to you, even if the Connecticut statute of limitations has otherwise expired.
If you claimed credit for taxes paid to another jurisdiction on your Connecticut return and you later amend the tax return for that jurisdiction or your income is changed or corrected by that jurisdiction, you must amend your Connecticut income tax return if the there is any effect to the credit you claimed on your Connecticut return. You must file Form CT-1040X within 90-days of the change or amendment (within 30 days for taxable years prior to 1998). If you file Form CT-1040X no later than 90 days after the final determination (within 30 days for taxable years prior to 1998), any Connecticut income tax overpayment resulting from the final determination will be refunded or credited to you, even if the Connecticut statute of limitations has otherwise expired.