2025 Connecticut Income Tax Forms
Printable CT State Tax Forms, Schedules, and Instructions
If you are preparing a Connecticut income tax return for the first time, start by identifying your residency status. Full-year residents generally use Form CT-1040. Part-year residents and nonresidents generally use Form CT-1040NR/PY. Choosing the right resident, part-year resident, or nonresident form matters because Connecticut uses different schedules and instructions to report income connected to the state.
Below you will find the most common 2025 Connecticut income tax forms, schedules, and instructions grouped by residency type. If you are not sure which residency status applies to you, review the CT-1040 instructions and CT-1040NR/PY instructions before choosing a form. As you complete your return, the form and line item instructions will tell you when to prepare additional schedules, credit forms, supporting worksheets, payment forms, or other Connecticut income tax forms.
2025 Full-Year Connecticut Resident Tax Forms
You are generally a full-year Connecticut resident if Connecticut was your permanent legal residence for the entire tax year. You may also be treated as a resident if you maintained a permanent place of abode in Connecticut for the entire year and spent a total of more than 183 days in the state. Full-year residents generally begin with Form CT-1040 and the CT-1040 instructions.
As you complete your Connecticut resident return, the form and line item instructions will tell you when to prepare additional schedules, credit forms, supporting worksheets, or payment forms.
| Form Code | Form Name |
|---|---|
| Form CT-1040 | Connecticut Resident Income Tax Return (includes Schedules 1 through 5) |
| Form CT-1040 Instructions | Form CT-1040 Instruction Booklet |
| Schedule CT-EITC | Connecticut Earned Income Tax Credit |
| Schedule CT-IT Credit | Income Tax Credit Summary |
2025 Part-Year Connecticut Resident Tax Forms
You are generally a part-year Connecticut resident if you changed your permanent legal residence by moving into or out of Connecticut during the tax year. Part-year residents generally begin with Form CT-1040NR/PY and the CT-1040NR/PY instructions. Some part-year residents may also need Schedule CT-1040AW or Schedule CT-SI to allocate income connected to Connecticut.
As you complete your Connecticut part-year resident return, the form and line item instructions will tell you when to prepare additional schedules, credit forms, supporting worksheets, or payment forms.
| Form Code | Form Name |
|---|---|
| Form CT-1040NR/PY | Connecticut Nonresident and Part-Year Resident Income Tax Return (includes Schedules 1 through 4) |
| CT-1040NR/PY Instructions | Form CT-1040NR/PY Instruction Booklet |
| Schedule CT-1040AW | Part-Year Resident Income Allocation |
| Schedule CT-SI | Connecticut Source Income Schedule for Nonresidents and Part-Year Residents |
2025 Connecticut Nonresident Tax Forms
You are generally a Connecticut nonresident if you were neither a resident nor a part-year resident during the tax year. Nonresidents who had Connecticut-source income generally begin with Form CT-1040NR/PY and the CT-1040NR/PY instructions. Some nonresident filers may also need Form CT-SI to report income from Connecticut sources.
As you complete your Connecticut nonresident return, the form and line item instructions will tell you when to prepare additional schedules, credit forms, supporting worksheets, or payment forms.
| Form Code | Form Name |
|---|---|
| Form CT-1040NR/PY | Connecticut Nonresident and Part-Year Resident Income Tax Return (includes Schedules 1 through 4) |
| CT-1040NR/PY Instructions | Form CT-1040NR/PY Instruction Booklet |
| Schedule CT-SI | Connecticut Source Income Schedule for Nonresidents and Part-Year Residents |
| Schedule CT-1040BA | Connecticut Nonresident Business Apportionment Schedule |
2025 Other Connecticut Individual Income Tax Forms
These Connecticut individual income tax forms may apply whether you file as a resident, part-year resident, or nonresident. They are less commonly used than the main return forms listed above, but they are necessary when the form or line item instructions ask you to include them.
Common situations include filing for an extension, amending a return, making a payment, claiming credits, changing an address, documenting withholding, or following up on a refund claim.
| Form Code | Form Name |
|---|---|
| CT-1040 Tax Tables | Connecticut Income Tax Tables to $102k |
| CT-1040 TCS | Connecticut Tax Calculation Schedule |
| Form CT-1040 EFW | Connecticut Electronic Withdrawal Payment Record |
| Form CT-1040ES | Connecticut Estimated Income Tax Payment Coupon for Individuals |
| Form CT-1040 EXT | Application for Extension of Time to File Connecticut Income Tax Return for Individuals |
| Form CT-1040V | Connecticut Electronic Filing Payment Voucher |
| Form CT-1040X | Amended Connecticut Income Tax Return for Individuals (includes Schedules 1 through 4) |
| Form CT-1040 CRC | Connecticut Claim of Right Credit |
| Form CT-1127 | Application for Extension of Time for Payment of Income Tax |
| Form CT-3911 | Taxpayer Statement Regarding State of Connecticut Tax Refund |
| Form CT-4852 | Substitute for Forms W-2 and 1099-R |
| Form CT-6251 | Connecticut Alternative Minimum Tax Return |
| Form CT-8379 | Connecticut Nonobligated Spouse Claim |
| Form CT-8857 | Connecticut Request for Innocent Spouse Relief |
| Schedule CT-1040WH | Connecticut Income Tax Withholding Supplemental Schedule |
| Schedule CT-CHET | Connecticut Higher Education Trust (CHET) 529 College Savings Plan Contribution |
Need More Connecticut Tax Forms?
The Connecticut tax forms you prepare will depend on your residency status, types of income, claimed credits, and whether you are making a payment or expecting a refund. Remember that if you earned income from more than one state, you may need to prepare an income tax return for each additional state. If you need a Connecticut form that is not listed above, visit the official Connecticut Department of Revenue individual income tax forms page for the complete state list.
Last updated: August 1, 2026
References:
- Individual Income Tax Forms. State of Connecticut, Connecticut Department of Revenue. Retrieved August 1, 2026.
- Connecticut Resident, Part-Year Resident, and Nonresident Tax Information. State of Connecticut, Connecticut Department of Revenue. Retrieved August 1, 2026.
- Form CT-1040 Connecticut Resident Income Tax Return. State of Connecticut, Connecticut Department of Revenue. Retrieved August 1, 2026.
- Form CT-1040 Connecticut Resident Income Tax Return Instructions. State of Connecticut, Connecticut Department of Revenue. Retrieved August 1, 2026.
- Form CT-1040NR/PY Connecticut Nonresident and Part-Year Resident Income Tax Return. State of Connecticut, Connecticut Department of Revenue. Retrieved August 1, 2026.
- Form CT-1040NR/PY Connecticut Nonresident and Part-Year Resident Income Tax Return Instructions. State of Connecticut, Connecticut Department of Revenue. Retrieved August 1, 2026.
- Chapter 229 Income Tax. Connecticut General Assembly, State of Connecticut. Retrieved August 1, 2026.