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Corporation Business Tax
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CT-1120 | CT-1120A | CT-1120ES | CT-1120EXT | CT-1120ATT |
CT-1120ATT(FY) | CT-1120AB | Schedule D | CT-1120K


CT-1120

The CT-1120, Corporation Business Tax Return, is used to compute tax both on a net income basis and on a capital stock basis.  Tax is paid on the basis that yields the higher tax.  The minimum tax is $250.    Form CT-1120 must be filed by every corporation or association taxable as a corporation that carries on business or has the right to carry on business in Connecticut.  Any corporation dissolved or withdrawn from Connecticut is subject to the corporation business tax up to the date of dissolution or withdrawal.  Corporations electing to file a combined return must also complete Form CT-1120CR, Combined Corporation Business Tax Return. For further instructions, click on the CT-1120 link above.

Schedule A | Schedule B | Schedule C | Schedule D | Schedule E | Schedule F | Schedule G


Schedule AComputation of Tax on Net Income

A corporation entitled to apportion its income must complete either Form CT-1120A, Corporation BusinessTax Return Apportionment Computation, or one of the special apportionment forms listed below:

  • Air carriers use Form CT-1120A-A, Corporation Business Tax Return Apportionment Computation – Air Carriers.

  • Motor bus companies and motor carriers engaged in multistate business use Form CT-1120A-BMC, Corporation Business Tax Return Apportionment Computation – Motor Bus and Motor Carrier Companies.

  • Financial service companies use Form CT-1120A-FS, Corporation Business Tax Return Apportionment Computation of Income From Financial Service Company Activities.

  • Manufacturers use Form CT-1120A-MFG, Corporation Business Tax Return Apportionment Computation – Manufacturing Companies.

  • Broadcasters and production entities use Form CT-1120A-BPE, Corporation Business Tax Return Apportionment Computation – Broadcasters and Production Entities.

  • Corporations that receive income from rendering securities brokerage services use Form CT-1120A-SBC, Corporation Business Tax Return Apportionment Computation – Securities Brokerage Services.

  • Corporations that receive income from credit card activities use Form CT-1120A-CCA, Corporation Business Tax Return Apportionment Computation of Income From Credit Card Activities.

  • If a corporation is a limited partner in one or more limited partnerships (other than an investment partnership) and is not otherwise carrying on or doing business in Connecticut, the partnership may elect for any income year to apportion its net income inside and outside the state as provided under the corporation business tax. Use Form CT-1120A-LP, Corporation Business Tax Return Apportionment of Limited Partnership Interests.

Line 1 - Enter the net income from Schedule D, Line 18.

Line 2 - Enter the appropriate apportionment fraction from Form CT-1120A, Schedule Q, Line 2; Schedule R, Line 6, Column C; or from the appropriate forms previously referenced. The fraction must be expressed as a decimal and carried to six places.

Line 3 - Enter the amount from Line 1 multiplied by Line 2, or enter the amount from Line 1, if not entitled to apportion.

Line 4 - Enter the amount of any unused losses from Form CT-1120 ATT, Corporation Business Tax Return Attachment, Schedule H, Line 10, Column D, attributable to Connecticut business operations as reported in years ending December 31, 2000, and thereafter.

Net operating losses incurred for income years beginning on or after January 1, 2000, may be carried forward for 20 successive income years. Losses may not be carried back. The loss entered here is limited to the loss attributed to Connecticut according to the method of apportionment prescribed in Conn. Gen. Stat. §12-218.

See Form CT-1120CR instructions for information about using carryforward losses on a combined return.

Line 5 - Subtract Line 4 from Line 3 and enter the result.

Line 6 - Multiply Line 5 by 7.5% (.075) and enter the result.


Schedule B - Computation of Minimum Tax on Capital

Use Schedule B to compute the minimum tax on the capital of a corporation. The minimum tax on capital does not apply to real estate investment trusts, regulated investment companies, or interlocal risk management agencies formed under Chapter 113a of the Connecticut General Statutes.

Line 1 - Enter the amount shown on Schedule E, Line 6, Column C.

Line 2 - Corporations, other than air carriers, enter the apportionment fraction from Form CT-1120A, Schedule S, Line 3, Column C. The fraction must be expressed as a decimal and carried to six places.

Line 3 - Enter the amount from Line 1 multiplied by Line 2, or enter the amount from Line 1, if not entitled to apportion.

Line 4 - Enter the number of months the corporation carried on business or had the right to carry on business in Connecticut, whichever is greater. A fractional part of a month is counted as a full month.

Line 5 - Multiply Line 3 by Line 4. Divide the result by 12 and enter the amount.

Line 6 - Multiply Line 5 by 0.31% (.0031) and enter the result. The maximum tax for Schedule B is $1,000,000.


Schedule C - Computation of Amount Payable

Line 1(a) - Enter the amount from Schedule A, Line 6; Schedule B, Line 6; or $250, whichever is greater.

Line 1(b) - Multiply Line 1(a) by 10% (.10) and enter the result. If the amount on federal Form 1120, Line 11 is less than $100 million or Line 1(a) is $250, enter zero.

Line 1(c) - If a corporation has received a notice from Connecticut Housing Finance Authority (CHFA) indicating that 60% or more of a revolving loan fund has not been properly loaned on or before the date three years after the date a revolving loan fund was established by such corporation, the credit amount specified in the notice must be recaptured. This amount should be reported on the first Form CT-1120 to be filed on or after the date of notice. If the fixed capital on account of which a  corporation claimed a Fixed Capital Investment tax credit is not held and used in Connecticut in the ordinary course of the corporation's trade or business in Connecticut for three full years following its acquisition, the corporation is required to recapture 100% of the amount of the credit allowed on the corporation business tax return required to be filed for the income year immediately following the income year during which the three-year period expires. If the fixed capital on account of which a corporation claimed the Fixed Capital Investment tax credit is not held and used in Connecticut in the ordinary course of the corporation’s trade or business in Connecticut for five full years following its acquisition, the corporation will be required to recapture 50% of the amount of the credit allowed on its corporation business tax return required to be filed for the income year immediately following the income year during which the five-year period expires.

Line 1 - Add Lines 1(a), 1(b), and 1(c), and enter the total. If no tax credits are being claimed, also enter this amount on Line 6.

Line 2 - Multiply Line 1 by 30% (.30) and enter the result.

Line 3 - Enter the greater of the amount on Line 2 or $250.

Line 4 - Subtract Line 3 from Line 1 and enter the result.

Line 5 - Enter the total tax credits applied from Form CT-1120K, Business Tax Credit Summary, Part II, Line 11. Do not exceed the amount on Line 4.

Line 6 - Subtract Line 5 from Line 1 and enter the result.

Line 7(a) - Enter the amount paid with Form CT-1120 EXT.

Line 7(b) - Enter the amount paid with estimate on Form CT-1120 ESA, ESB, ESC, or ESD.

Line 7(c) - Enter the amount of any overpayment from the prior year.

Line 7 - Add Lines 7(a), 7(b), and 7(c), and enter the total.

Line 8 - Subtract Line 7 from Line 6 and enter the result.

Line 9(a) - Enter penalty if applicable. See Interest and Penalties.

Line 9(b) - Enter interest due on tax not paid by the original due date. See Interest and Penalties.

Line 9(c) - Enter interest due on underpayment of estimated tax. Complete and attach Form CT-1120I.

Line 9 - Add Lines 9(a), 9(b), and 9(c) and enter the total.

Line 10(a) - Enter the amount of overpayment to be credited to 2007 estimated tax. Overpayment of tax liability for a preceding income year is credited against the current estimated tax liability as of the receipt date of a completed tax return and not a tentative tax return. An overpayment cannot be determined to exist until a completed return is filed.  Overpayments will be treated as estimated tax paid on March 15, if the tax return is filed by March 15. Your request to apply an overpayment to the following tax year is irrevocable.

Line 10(b) - Enter the amount of overpayment to be refunded.

Line 10 - Add Line 10(a) and Line 10(b) and enter the total.

Line 11 - Balance Due - Add Line 8 and Line 9, and enter the total.


Schedule DComputation of Net Income

Line 4 - Enter the amount of interest expenses paid to a related member as reported on Form CT-1120AB, Part I A, Line 1.

Line 5 - Enter the amount of intangible expenses paid to a related member as reported on Form CT-1120AB, Part I B, Line 1.

Line 12 - Enter the amount of exceptions to interest add back as reported on Form CT-1120AB, Part II A, Line 1.

Line 13 - Enter the amount of exceptions to interest add back as reported on Form CT-1120AB, Part II A, Line 2.

Line 14 - Enter the amount of exceptions to interest add back as reported on Form CT-1120AB, Part II A, Line 3.

Line 15 - Enter the amount of exceptions to the add back of intangible expenses paid to a related member as reported on Form CT-1120AB, Part II B, Line 1.


Schedule EComputation of Minimum Tax Base

Line 1 - Enter the beginning (Column A) and ending (Column B) values of the issued and outstanding capital stock including treasury stock at par or face value, fractional shares, scrip certificates, and payments on subscriptions. (See federal Form 1120, Schedule L, Line 22a and Line 22b.)

Line 2 - Enter the beginning (Column A) and ending (Column B) values of paid-in or capital surplus, including retained earnings. Any deficit must be reported as a negative number. (See federal Form 1120, Schedule L, Lines 23, 24, and 25.)

Line 3 - Enter the beginning (Column A) and ending (Column B) values of all surplus reserves (including deferred taxes). Attach a schedule of all surplus reserves to support the amounts shown on Line 3.

A reserve is an amount set aside or deducted from current or retained earnings for meeting future liabilities.

Line 4 - Add Lines 1, 2, and 3 in both Column A and Column B. Enter in Column C the average of Column A and Column B.

Line 5 - Enter the total holdings of stock in Column A and Column B. Enter the average of Column A and Column B on Line 5, Column C. Attach a schedule that lists the beginning and ending book values of total holdings of stock of private corporations, including treasury stock. The total book value of shares must equal the amount claimed as a deduction on Schedule E, Line 5. The book value of stock does not include the value of other assets acquired and held in connection with or incidental to the ownership of such stock.

Private corporations means all non-governmental corporations, whether closely or publicly held.

Line 6 - Subtract Line 5, Column C, from Line 4, Column C. Enter the result here and on Form CT-1120, Schedule B, Line 1.


   Schedule F Taxes

Conn. Gen. Stat. §12-217 disallows any deduction for the Connecticut corporation business tax and any deduction for taxes imposed on or measured by income or profits by any state, political subdivision, or the District of Columbia.

Line 1 - Enter in Column A all payroll taxes deducted in arriving at federal taxable income.

Line 2 - Enter in Column A all real property taxes deducted in arriving at federal taxable income.

Line 3 - Enter in Column A all personal property taxes deducted in arriving at federal taxable income.

Line 4 - Enter in Column A all sales and use taxes deducted in arriving at federal taxable income.

Line 5 - Enter in Column A any other taxes not based on income or profits deducted in arriving at federal taxable income.

Line 6 - Enter in Column B the amount of Connecticut corporation business tax deducted in arriving at federal taxable income.

Line 7 - Enter in Column B any corporate tax imposed on or measured by income or profits by any state (other than Connecticut) or political subdivision, or the District of Columbia, deducted in the computation of federal taxable income.

Line 8 - Add the amounts on Line 6 and Line 7 in Column B. Enter the total here and on Schedule D, Line 3.


Schedule G - Additional Required Information

Attach a schedule of corporate officers' names, complete home addresses, and corporate titles.

Line 1 - Enter the Connecticut towns in which the corporation owns or leases (as lessee) real or tangible personal property or performed any services.

Line 2(a) - If the corporation transferred a controlling interest in an entity where the entity owns, directly or indirectly, an interest in Connecticut real property, the corporation (the transferor) may be subject to the controlling interest transfer tax. Enter the name and FEIN of the entity in which a controlling interest was transferred. The transferor is required to file Form AU-330, Controlling Interest Transfer Taxes. (Conn. Gen. Stat. §12-638b)

Line 2(b) - If this corporation owned Connecticut real property and was the entity in which a direct or indirect controlling interest was transferred, enter the name and FEIN of the transferor. The transferor may be subject to the controlling interest transfer tax. The entity in which a direct or indirect controlling interest was transferred is required to file Form AU-331, Controlling Interest Transfer Taxes Informational Return.

Line 3 - If any other corporation owns a majority of the voting stock of this corporation, enter the name and FEIN of the corporation.

Line 4 - Enter the last taxable year this corporation was audited by the IRS. Corrections to taxable income by the IRS must be reported to the Commissioner of Revenue Services on or before 90 days after the final determination of the change.

All federal adjustments must be reported using Form CT-1120X.


CT-1120A

The CT-1120A, Corporation Business Tax Return Apportionment Computation, is used to compute the apportionment factors for the net income and the minimum tax base. For further information, go to the CT-1120A instructions, including instructions for Schedules Q, R and S.


CT-1120ES

The CT-1120ES, Estimated Corporation Business Tax Payment, is used to make a quarterly estimated Corporation Business Tax payment.  Every corporation carrying on business or having the right to carry on business in Connecticut whose estimated current year tax liability, as shown on Schedule 1, Line 4, is more than $1,000 must pay estimated tax payments in four installments.  For further information, go to the CT-1120ES instructions.


CT-1120EXT

The CT-1120EXT, Application for Extension of Time to File Corporation Business Tax Return, is required to obtain an extension of time to file Form CT-1120, Form CT-1120CR or Form CT-1120U. To get an extension of time to file an annual return, the corporation must file Form CT-1120EXT not later than the first day of the month following the due date of the company’s corresponding federal income tax return for the income year (April 1 for calendar year taxpayers).  In the case of any company not required to file a federal income tax return for the income year, the extension request must be filed on or before the first day of the fourth month following the end of the income year.  Payment of the total tax due must be included with the request. The timely filing of Form CT-1120EXT will automatically extend the due date for six months. For further information go to the CT-1120EXT instructions.


CT-1120ATT

The CT-1120ATT, Corporation Business Tax Return Attachment, contains the following computation schedules:

  • Schedule H, Connecticut Apportionment Operating Loss Carryover;

  • Schedule I, Dividend Deduction; and

  • Schedule J, Bonus Depreciation Recovery.

For further information, go to the CT-1120ATT instructions.  Fiscal year filers (other than calendar year) go to the CT-1120ATT(FY)


CT-1120AB 

The CT-1120AB, Add Back and Exceptions to Add Back of Interest and Intangible Expenses, must be completed by each corporation that pays interest and intangible expenses to a related party.  For further information, go to the CT-1120AB instructions.


CT-1120K

The CT-1120K, Business Tax Credit Summary, is used to summarize a corporation’s claim for available business Tax credits.  Additional information about Connecticut tax credits is available in Informational Publication 2004(20), Guide to Connecticut Business Tax Credits.  The amount of tax credits otherwise allowable against the corporation business tax for any income year shall not exceed 70% (.70) of the amount of tax due prior to the application of the tax credit.  No tax credit can be applied against the minimum tax of $250.  For further information, go to the  CT-1120K instructions.