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Composite Income Tax
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A PE is required to file Form CT-1065/CT-1120SI, Connecticut Composite Income Tax Return, and is also required to make a composite Connecticut income tax payment on behalf of each nonresident member where:  (1) the member’s pro rata share of the PE's income derived from or connected with Connecticut sources is $1,000 or more; and (2) an election to be included on Form CT-G, Connecticut Group Income Tax Return, has not been made by such nonresident member.  A nonresident member may not elect out of the composite payment requirements. 

For a more detailed line description and instruction, please review the CT-1120SI/CT-1065 instructions booklet.

% Ownership - When entering the percent of ownership on the Member Information Page, use a decimal.  E.G. 25% should be entered as .2500.  100% should be entered as 1.0000

Pass-Through Entity Name:  Enter the legal name of the business.

CT REG: If the business is registered with DRS, enter your CT REG here.  Your CT REG is the unique number (10-13 digits long) assigned by DRS and is found on all returns and correspondence from DRS.

Extension Form (CT-1120SI/CT1065EXT)

To get a six-month extension of time to file form CT-1065/CT-1120SI and the same extension of time to furnish schedule CT K-1 to its members, the pass-through entity (PE) must file Form CT-1065/CT 1120SI EXT, Application for extension of time to file Connecticut Composite Income Tax Return, no later than the fifteenth day of the fourth month following the close of the taxable year together with payment of the total tax due.  Timely filing this form automatically extends the due date for six months only if federal Form 7004, Application for Automatic 6-month Extension of Time to File Certain Business Income Tax, Information and Other Returns has been filed with the Internal Revenue Service (IRS). If federal Form 7004 was not filed, a PE may apply for a six-month extension to file Form CT-1065/CT-1120SI only if there is a reasonable cause for the request.  Form CT-1065/CT-1120SI EXT extends only the time to file a return. It does not extend the time to pay the amount of income tax due.