CT State Tax Information

Who Needs to File?

You must file a CT state income tax return if any of the following is true for the taxable year:

  • you had CT income tax withheld, or
  • you had made estimated tax payments to CT, or
  • you meet the Gross Income Test, or
  • you had a federal alternative minimum tax liability

If none of the above apply, do not file a CT state income tax return.

Gross Income Test

You must file a CT state income tax return if your gross income for the entire tax year exceeds:

  • $12,000 and you will file as married filing separately or civil union filing separately, or
  • $13,000 and you will file as single, or
  • $19,000 and you will file as head of household, or
  • $24,000 and you will file as married filing jointly, civil union filing jointly, or qualifying widow(er) with dependent child

 

Tax Status for CT State Purposes

In any calendar year, you could have a different status for (1) immigration, (2) federal income tax purposes, and (3) state income tax purposes.

For information about "non-resident" vs. "resident" for CT income tax purposes, refer to the CT Income Tax Instructions.

CT Forms and Publications

CT Department of Revenue Services (DRS) no longer processes state income tax returns without an SSN or ITIN. If you have not received your ITIN before the tax deadline of April 15, you should still file your return without the ITIN, pay any tax due, and attach a copy of your ITIN application (form W-7) that you submitted with your federal return.

Income tax treaty provisions are disallowed for CT state income tax purposes. Therefore, any treaty income reported on your federal 1040NR or 1040NR-EZ must be added to your federal Adjusted Gross Income (AGI) on your CT-1040 (calculations are done on CT Schedule 1, line 38, write in tax treaty wages, then go to line 2 of CT-1040). For complete information, refer to Special Instructions for Nonresident Aliens of the CT Income Tax Instructions.

Resident Forms
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Complete Form CT-1040EZ or CT-1040; if you have filed in CT the previous tax year, you will be eligible to Telefile or Webfile (see front of CT Income Tax Instructions publication)

See all resident forms here.

  

Non-Resident or Part-Year
Resident Forms
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Complete CT-1040NR/PY; this form is usually used by people who have lived and/or worked in multiple states or resided in CT for less than 183 days in that calendar year

See all non-resident forms here.

Other Forms
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CT Tax Tables

All other CT state tax forms

Other State Tax Information

If you earned income in another state, you may need to file a state return for the state in which you earned income. You will need to refer to the information from that particular state's Department of Revenue.