Current Corporation Forms

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2017 Corporation Tax Forms

Booklets

Name	Description	Revised Date
CT-1120	2017 Connecticut Corporation Business Tax Instructions	01/2018

Business Tax Returns

Name	Description	Revised Date
CT-1120	2017 Corporation Business Tax Return	12/2017
CT-1120A	Corporation Business Tax Return Apportionment Computation (with instructions)	12/2017
CT-1120 ATT	Corporation Business Tax Return Attachment Schedules H, I, and J (with instructions)	12/2017
CT-1120AB	Add Back and Exceptions to Add Back of Interest and Intangible Expenses	12/2016
CT-1120K	Business Tax Credit Summary	12/2017
CT-1120I	Computation of Interest Due on Underpayment of Estimated Tax (with instructions)	12/2017
CT-1120 EXT	Application for Extension of Time to File Corporation Business Tax Return (with instructions)	12/2017
CT-1120 ES	2017 Estimated Corporation Business Tax Payment Coupons	01/2017
CT-1120 ES	2018 Estimated Corporation Business Tax Payment Coupons	12/2017
CT-1120X	Amended Corporation Business Tax Return	12/2017
CT-1120X	Amended Corporation Business Tax Return (Instructions)	12/2017
CT-1120 CU BOOKLET	2017 Combined Unitary Corporation Business Tax Booklet	01/2018
CT-1120 CU	2017 Combined Unitary Corporation Business Tax Return	12/2017
CT-1120A-CU	2017 Apportionment Computation for Combined Unitary Filers	12/2017
CT-1120CU-NI	2017 Tax on Combined Group Net Income	12/2017
CT-1120CU-MTB	2017 Tax on Combined Group Minimum Tax Base	12/2017
CT-1120CU-MI	2017 Combined Group Member Information	12/2017
CT-1120CU-NCB	2017 Nexus Combined Base Tax Calculation	12/2017

Other Corporation Forms

Name	Description	Revised Date
AU-796	Reinstatement Guarantee Declaration for Non-stock Corporations	03/2008
AU-797	Dissolution Guarantee Declaration for Stock Corporations	04/2008
AU-800a	Withdrawal Guarantee Declaration for Corporations	03/2008
AU-801	Reinstatement Guarantee Declaration for Stock Corporations	03/2008
CT-1120A-A	Corporation Business Tax Return Apportionment Computation-Air Carriers	03/2017
CT-1120 A-BMC	Corporation Business Tax Return Apportionment Computation - Motor Bus and Motor Carrier Companies	12/2016
CT-1120 A-BPE	Corporation Business Tax Return Apportionment Computation - Broadcasters and Production Entities	12/2016
CT-1120 A-CCA	Corporation Business Tax Return Apportionment Computation of Income from Credit Card Activities	12/2016
CT-1120 A-FS	Corporation Business Tax Return Apportionment Computation of Income from Financial Service Companies Activities	12/2017
CT-1120 A-IRIC	Corporation Business Tax Return Apportionment Computation of Income from Services to Regulated Investment Companies	12/2016
CT-1120 A-LP	Corporation Business Tax Return Apportionment of Limited Partnership Interests	12/2017
CT-1120 A-SBC	Corporation Business Tax Return Apportionment Computation - Securities Brokerage Services	12/2016
CT-1120 PIC	Information Return for Passive Investment Companies	12/2017

Credit Forms

Name	Description	Revised Date
CT-1120 AT	Apprenticeship Training Tax Credit	12/2017
CT-1120 DA	Digital Animation Tax Credit	12/2017
CT-1120 DL	Donation of Land Credit	12/2017
CT-1120 EDPC	Electronic Data Processing Equipment Property Tax Credit	12/2017
CT-1120 FCIC	Fixed Capital Investment Credit	12/2017
CT-1120FP	Film Production Tax Credit	12/2017
CT-1120 FPI	Film Production Infrastructure Tax Credit	12/2017
CT-1120 GB	Green Building Tax Credit	12/2017
CT-1120 HCIC	Human Capital Investment Credit	12/2017
CT-1120 HH	Historic Homes Rehabilitation Tax Credit	12/2017
CT-1120 HP	Historic Preservation Tax Credit	12/2017
CT-1120 HPC	Housing Program Contribution Credit	12/2017
CT-1120 HR	Historic Rehabilitation Tax Credit	12/2017
CT-1120 HS	Historic Structures Rehabilitation Tax Credit	12/2017
CT-IRF	Insurance Reinvestment Fund Credit	12/2017
CT-1120 MEC	Machinery and Equipment Expenditure Credit	12/2017
CT-1120 RC	Research and Experimental Expenditures Credit	12/2017
CT-1120 RDC	Research and Development Credit	12/2017
CT-1120 SBA	Small Business Guaranty Fee Tax Credit	12/2017
CT-1120SF	Service Facility Credit	12/2017
CT-1120 TIC-EZ	Manufacturing Facility Credit for Facilities Located in a Targeted Investment Community/Enterprise Zone NOTE: This form replaces Forms CT-1120CRMC, CT-1120CRMCEZ, CT-1120MC and CT-1120MCEZ	12/2017
CT-UISR	Urban and Industrial Site Reinvestment Credit	12/2017
CT-1120 XCH	Application for Exchange of Research and Development or Research and Experimental	12/2017

Connecticut State Department of Revenue Services

2017 Corporation Tax Forms

Booklets

Other Corporation Forms