Connecticut DRS Form Instructions
- ct-1040 Instructions for Form CT-1040 — Connecticut Resident Income Tax Return
- ct-1040-ext Form CT-1040 EXT — Application for Extension of Time to File Connecticut Income Tax Return for Individuals
- ct-1040-nrpy Instructions for Form CT-1040NR/PY — Nonresident & Part-Year Resident Income Tax Return
- ct-1040es Form CT-1040ES — Estimated Connecticut Income Tax Payment Coupon for Individuals (2026)
- ct-1040x Form CT-1040X — Amended Connecticut Income Tax Return for Individuals
- ct-1041 Instructions for Form CT-1041 — Connecticut Income Tax Return for Trusts and Estates
- ct-1041-ext Form CT-1041 EXT — Application for Extension of Time to File Connecticut Income Tax Return for Trusts and Estates
- ct-1041es Form CT-1041ES — Estimated Connecticut Income Tax Payment Coupon for Trusts and Estates (2026)
- ct-1065-ct-1120si Instructions for Form CT-1065/CT-1120SI — Connecticut Composite Income Tax Return
- ct-1065-ct-1120si-ext Form CT-1065/CT-1120SI EXT — Application for Extension of Time to File Connecticut Pass-Through Entity Tax Return (Composite)
- ct-1120 Instructions for Form CT-1120 — Corporation Business Tax Return
- ct-1120-att Form CT-1120 ATT — Corporation Business Tax Attachment Schedules
- ct-1120-ext Form CT-1120 EXT — Application for Extension of Time to File Connecticut Corporation Business Tax Return
- ct-1120a Form CT-1120A — Apportionment Computation
- ct-1120cu Instructions for Form CT-1120CU — Combined Unitary Corporation Business Tax Return
- ct-1120es Form CT-1120ES — Estimated Corporation Business Tax Payment Coupon (2026)
- ct-1120i Form CT-1120I — Computation of Interest Due on Underpayment
- ct-941 Form CT-941 — Connecticut Quarterly Reconciliation of Withholding
- ct-pet Instructions for Form CT-PET — Pass-Through Entity Tax Return
- ct-pet-es Form CT-PET ES — Estimated Connecticut Pass-Through Entity Tax Payment Coupon (2026)
- ct-pet-ext Form CT-PET EXT — Application for Extension of Time to File Connecticut Pass-Through Entity Tax Return
- o-88 Form O-88 — Instructions for Form OS-114 (Sales and Use Tax)
- os-114 Form OS-114 — Connecticut Sales and Use Tax Return
- schedule-ct-k-1 Schedule CT K-1 — Member's Share of Connecticut Income, Credits, and Deductions
- schedule-ct-pe Schedule CT-PE — Pass-Through Entity Tax Credit