Schedule CT-SI: Nonresident or Part-Year Resident Schedule of Income from Connecticut Sources (Revision 2024-12)
Connecticut · Connecticut DRS · Used for tax years 2024
Schedule CT-SI is Connecticut’s 2024 income schedule for nonresidents and part-year residents. It reports income from Connecticut sources and related adjustments to calculate the amount entered on Form CT-1040NR/PY, Line 6.
Who files this form
Complete Schedule CT-SI for tax year 2024 if you were a nonresident or part-year resident of Connecticut. Attach it to Form CT-1040NR/PY.
- Nonresidents: Enter income received from Connecticut sources.
- Part-year residents: Complete Schedule CT-1040AW, Part-Year Resident Income Allocation, to determine the amounts to enter.
What you'll need
Have these forms and details available:
- Form CT-1040NR/PY, to which you must attach Schedule CT-SI.
- Schedule CT-1040AW, if you were a part-year resident.
- Your name and Social Security number, plus your spouse’s information if filing jointly.
- Amounts of Connecticut-source income and adjustments directly related to that income.
- Working days inside and outside Connecticut, nonworking days, and total income being apportioned if you need the Employee Apportionment Worksheet. The worksheet also allows a basis other than working days.
- The recipient’s last name and Social Security number if entering alimony paid on Line 24.
How to file
Attach the completed 2024 Schedule CT-SI to Form CT-1040NR/PY. Use blue or black ink only, and do not use staples.
Enter Schedule CT-SI, Line 30, on Form CT-1040NR/PY, Line 6.
The form directs you to visit Connecticut’s Individual Income Tax page before completing the schedule. The supplied text does not provide a mailing address or e-filing instructions.
Common mistakes
- Using the wrong year’s form: The form warns that submitting the correct year’s form is necessary to prevent processing delays. Use the 2024 edition for tax year 2024.
- Using staples or another ink color: Do not use staples. Complete the schedule in blue or black ink only.
- Completing the Employee Apportionment Worksheet when the exact amount is known: Do not complete Lines A through G if you know your exact Connecticut-source employment income. Complete them only when employment income was earned both inside and outside Connecticut and the exact Connecticut amount is unknown.
- Including unrelated adjustments: Part 2 directs you to enter only adjustments directly related to the income reported above.
Questions people ask
How do part-year residents transfer amounts from Schedule CT-1040AW?
Add Columns B and D for each line of Schedule CT-1040AW, then enter the totals on Schedule CT-SI, Lines 1 through 30.
How does the Employee Apportionment Worksheet calculate Connecticut income?
Add working days outside Connecticut on Line A and working days inside Connecticut on Line B to get Line C. Divide Line B by Line C and round to four decimal places for Line E. Multiply Line E by the total income being apportioned on Line F. Enter the result on Line G and Schedule CT-SI, Line 1.
How do I calculate income from Connecticut sources on Line 30?
Add Lines 1 through 14 to get gross income on Line 15. Add adjustments on Lines 16 through 28 to get Line 29. Subtract Line 29 from Line 15 and enter the result on Line 30.
Where does the Line 30 amount go on my return?
Enter it on Form CT-1040NR/PY, Line 6, and attach Schedule CT-SI to that return.