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File Connecticut
State Business Tax Extension Form

Connecticut (CT) Requires:

  • Businesses (Corporation, Partnerships, S-Corporations, and fiduciaries) to file a separate business income tax extension form to get an extension of time to file Connecticut Business income tax return.
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IRS Authorized E-file Provider for Tax Extension Forms

ExpressExtension supports the filing of Form CT 1120-EXT, CT-1041 EXT with the State of Connecticut.


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An Overview of Connecticut State Business Income Tax Extension Forms

- Updated Feb 08, 2024 - 8.00 AM by Admin, ExpressExtension

Connecticut (CT) Requires:

  • If you’re a Corporation, file Form CT-1120 EXT to request 6-month extension to file Corporation business tax return, or Combined Unitary Corporation business tax return.
  • If you’re a Partnership or S-corporation, file Form CT-1065/CT-1120SI EXT to request a
    6-month extension to file Partnerships and S-Corporations income tax return.
  • If you’re a Fiduciary, file Form CT-1041 EXT to request a 5 1/2 month extension to file trusts and estates income tax return.

Does Connecticut accept my approved federal business tax extension, or do they require a state extension form?

No, in addition to filing a Form 7004 with the IRS, you will need to file a separate extension form with Connecticut's state department to get an extension of time to file the Connecticut's business income tax return.

Note: If you have already filed federal Form 7004, then you no need to provide any 'reason' while filing a state extension form. However, the reason is mandatory if federal Form 7004 was not applied.

What extension form does the State of Connecticut require?

Corporations

Businesses in Connecticut that operate as corporations are required to file Form CT-1120 and Form CT-1120 CU with the state each year. If you cannot file Form CT-1120 and Form CT-1120 CU with the state on time, you can file Form CT-1120 EXT with the state to request an extension of 6 months to file your business income tax return.

  • Form CT-1120EXT - Request for Six-Month Extension to File (for C Corporation)

S-Corporations and Partnerships

Businesses in Connecticut that operate as either an S-Corporation or Partnership are required to file either Form CT-1120SI or Form CT-1065, the business income tax returns for pass-through entities. If you need more time to complete your business income tax returns, you can file the Form CT-1065 EXT/ Form CT-1120SI EXT to extend your deadline for up to 6 months.

Note: Form CT-1065/CT-1120SI EXT must be filed electronically through DRS Taxpayer Service Center (TSC) at https://portal.ct.gov/TSC.

Trust and estates

Businesses in Connecticut that operate as Trust and estates are required to file Form CT-1041, with the state by the original due date. If you cannot file Form CT-1041 on time, file Form CT-1041 EXT, to request a five and a half‑month extension to file your Connecticut income tax return for trusts and estates.

What is the deadline to file an extension with Connecticut?

Connecticut General Corporation Tax Extension

The Deadline to file CT-1120 EXT with the State of Connecticut is the fifteenth day of the month following the due date of the federal return (May 15 for calendar
year taxpayers)
.

Exception for June 30th year ends: If your corporation has a June 30th year end, the due date to request an extension is 15th day of 4th month after year end
(October 15th)
.

Form CT-1120 EXT grants an automatic 6-month extension of time to file
Form CT-1120
.

Connecticut Pass Through Entity Extension

The due date to file Form CT-1120SI EXT and Form CT-1065 EXT with the State of Connecticut is 15th day of the 3rd month after the tax year ends (March 15 for calendar year taxpayers)

Form CT-1065/CT-1120SI EXT grants an automatic 6-month extension of time to file Form CT-1065/CT-1120SI.

Trust and estates

The due date to file Form CT-1041 EXT with the State of Connecticut is 15th day of the 4th month after the tax year ends (April 15 for calendar year taxpayers)

How do I pay my balance due?

Remember, your extension of time applies only to your tax return, not your tax payment. You need to pay your tax due by the original due date with your extension request by using any one of the following options:

Note: If you cannot file and pay electronically, you can request a waiver. For this visit portal.ct.gov/DRS and complete Form DRS-EWVR, Electronic Filing and Payment Waiver Request.

Once you receive a waiver from the electronic payment requirement, make your check payable to the Commissioner of Revenue Services. Be sure to sign your check and paper clip it to the front of your return. Do not send cash.

Where do I mail the extension Form CT-1120EXT?

Mail Form CT-1120EXT, Application for Extension of Time to File an Connecticut Income Tax Return for Corporation to:

Mail paper return with payment to:

Address Icon
Department of Revenue Services State of Connecticut,
P.O. Box 2974,
Hartford, CT 06104-2974.

Mail paper return without payment to:

Address Icon
Department of Revenue Services State of Connecticut,
P.O. Box 150406,
Hartford, CT 06115-0406.

Where do I mail the extension Form CT-1041 EXT?

Mail Paper return with or without payment to:

Address Icon
Department of Revenue,
State of Connecticut,
P.O. Box 2934,
Hartford, CT 06104-2934.

Mail Payments without tax forms to:

Address Icon
Department of Revenue
State of Connecticut,
P.O. Box 5088,
Hartford, CT 06102-5088.
Published by ExpressExtension Support, ExpressExtension Last modified 12/07/2021
6:45:10 AM EST