Walk-in services at all DRS branch office locations remain suspended. Email DRS at drs@po.state.ct.us. Email the Priority One Taxpayer Assistance Program: DRSPriorityOne_CollectionsAssist@po.state.ct.us. Please check our Frequently Asked Questions page.

Correcting a CT Income Tax Return

ALERT: RECENTLY ENACTED FEDERAL LEGISLATION MAY IMPACT CERTAIN CONNECTICUT TAXPAYERS - for more information, click here.

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.


When must an amendment be filed in order to claim a refund?

Purpose: Use a Form CT-1040X to amend a previously filed Connecticut income tax return for individuals. Visit the DRS Taxpayer Service Center (TSC) at portal.ct.gov/TSC to file Form CT-1040X online.

If Form CT-1040X is filed in order to have an overpayment of Connecticut income tax refunded or credited, it must be filed before the Connecticut statute of limitations expires. Generally, the Connecticut statute of limitations for refunding or crediting any Connecticut income tax overpayment expires three years after the due date of the return, but if a timely request for an extension of time to file a return was filed, the statute of limitations expires three years after the extended due date of the return or three years after the date of filing the return, whichever is earlier. If you were required to file an amended return, but failed to do so, a penalty may be imposed. Interest will also be assessed on any additional Connecticut income tax not paid on or before the due date.

You must file Form CT-1040X in the following circumstances:

 1.  The IRS or federal courts change or correct your federal income tax return and the change or correction results in your Connecticut income tax being overpaid or underpaid.

File Form CT-1040X no later than 90 days after final determination.

If you file Form CT-1040X no later than 90 days after the date of 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.

2. You filed a timely amended federal income tax return and the amendment results in your Connecticut income tax being overpaid or underpaid.

File Form CT-1040X no later than 90 days after final determination.

If you file Form CT-1040X no later than 90 days after the date of 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.

 3. You claimed a credit for income tax paid to a qualifying jurisdiction on your original income tax return and the tax officials or courts of the qualifying jurisdiction made a change or correction results in your Connecticut Income Tax being overpaid or underpaid (by increasing or decreasing the amount of your allowable credit).

File Form CT-1040X no later than 90 days after final determination.

If you file Form CT-1040X no later than 90 days after the date of 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.

 4. You claimed a credit for income tax paid to a qualifying jurisdiction on your original income tax return and you filed a timely amended income tax return with that qualifying jurisdiction and the amendment results in your Connecticut income tax being overpaid or underpaid (by increasing or decreasing the amount of your allowable credit).

File Form CT-1040X no later than 90 days after final determination.

If you file Form CT-1040X no later than 90 days after the date of 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.

 5. If none of the above circumstances apply, but you made a mistake or omission on your Connecticut income tax return and the mistake or omission results in your Connecticut income tax being overpaid or underpaid.  File Form CT-1040X no later than three years after the due date of your return, or if you filed a timely request for an extension of time to file, three years after the date of filing the return or three years after the extended due date, whichever is earlier.

Do not file Form CT-1040X
for any of the following reasons:

  • To have an overpayment refunded instead of applied to next year’s estimated tax or to change your contributions to designated charities. These elections that you made on your original return cannot be changed by filing Form CT-1040X.
  • To amend your Connecticut income tax return for an earlier year to claim a credit for income tax paid on income included in your Connecticut adjusted gross income for that year and repaid in a later taxable year. File Form CT-1040CRC, Claim of Right Credit, with your Connecticut income tax return for the later taxable year.

Financial Disability

If you are financially disabled, as defined in IRC §6511(h)(2), the time for having an overpayment of Connecticut income tax refunded or credited to you is extended for as long as you are financially disabled. You are considered financially disabled if you are unable to manage your own affairs by reason of a medically determinable physical or mental impairment that has lasted or can be expected to last for a continuous period of not less than 12 months. You are not considered financially disabled during any period that your spouse or any other person is authorized to act on your behalf in financial matters. See Policy Statement 2001(14), Claims for Refund Made by Financially Disabled Individuals.