New York Form IT-203-C, Nonresident or Part-Year Resident Spouse’s Certification, is used by married taxpayers who file a joint New York nonresident or part-year resident return on Form IT-203 when only one spouse has New York source income. This form helps New York identify which spouse earned the income reported in the New York State amount column and which spouse had no New York source income for the tax year. The form is important because married nonresidents or part-year residents filing a joint New York return may need to use the combined income of both spouses to calculate the base tax, even when only one spouse earned income from New York sources. However, the spouse with no New York source income is not required to sign the joint New York return and cannot be held responsible for New York tax, penalties, or interest that may be due. Form IT-203-C gives the spouse with New York source income a way to certify that the other spouse had no New York source income. It also helps make sure names and Social Security numbers are entered correctly on Form IT-203 and any payment voucher used with the return.
How To File New York Form IT-203-C
File Form IT-203-C with Form IT-203. Do not file it by itself. The spouse with New York source income must complete and sign the certification. After completing the form, attach it to the New York nonresident or part-year resident income tax return. Keep a copy with your tax records. Make sure the name and Social Security number order matches the rules for Form IT-203-C, Form IT-203, and Form IT-201-V if a payment voucher is used.

How To Complete New York Form IT-203-C
Complete this form only if you are filing a joint Form IT-203 and only one spouse had New York source income. Enter the spouse with New York source income first. Enter the spouse with no New York source income second. The certification must be signed by the spouse who has New York source income. Do not have the spouse with no New York source income sign this certification unless another form or separate situation requires it. Review all names, Social Security numbers, the tax year, signature, and date before filing.
Who Must Complete New York Form IT-203-C?
You must complete Form IT-203-C if you are required to file a joint Form IT-203 and only one spouse had New York source income. The spouse who had New York source income is the person who completes and signs the form.
Name And Social Security Number Rules
Form IT-203-C Name Order: Enter the name and Social Security number of the spouse with New York source income first. Then enter the name and Social Security number of the spouse with no New York source income second.
Form IT-203 Name Order: On Form IT-203, enter the name and Social Security number of the spouse with New York source income first. Then enter only the Social Security number of the spouse with no New York source income second. Do not enter the name of the spouse with no New York source income on Form IT-203.
Form IT-201-V Payment Voucher Rule: If you file Form IT-201-V, enter only the name and Social Security number of the spouse with New York source income. Do not enter the name or Social Security number of the spouse with no New York source income on the payment voucher.
New York Form IT-203-C Line By Line Instructions
Name Of Spouse With New York Source Income: Enter the full name of the spouse who had income from New York sources during the tax year. This name must be listed first.
Social Security Number For Spouse With New York Source Income: Enter the Social Security number of the spouse who had New York source income. Make sure it matches the number used on Form IT-203.
Name Of Spouse With No New York Source Income: Enter the full name of the spouse who had no New York source income during the tax year. This name must be listed second on this form.
Social Security Number For Spouse With No New York Source Income: Enter the Social Security number of the spouse who had no New York source income.
Certification Of Spouse With New York Source Income: The spouse with New York source income must certify that they are the spouse whose New York source income is shown in the New York State amount column on Form IT-203. They also certify that, to the best of their knowledge and belief, the other spouse had no New York source income for the tax year.
Tax Year: Enter the tax year covered by the certification. Use the same tax year as the Form IT-203 return.
Signature: The spouse with New York source income must sign the form. The signature confirms the certification statement.
Date: Enter the date the spouse with New York source income signs the form.
Purpose Of The Form
Form IT-203-C is used to help process a joint New York return when both spouses are included in the income calculation but only one spouse has New York source income. The combined income of both spouses may be used to determine the base tax subject to income percentage allocation. However, the spouse with no New York source income does not have to sign the joint return and is not liable for any New York tax, penalty, or interest that may be due.
Final Review Before Filing
Check that the spouse with New York source income is listed first. Confirm that the spouse with no New York source income is listed second. Make sure both Social Security numbers are correct. Review the certification statement, tax year, signature, and date. If you are also using Form IT-201-V, make sure only the spouse with New York source income is listed on that payment voucher. Attach the completed Form IT-203-C to Form IT-203 and keep a copy for your records.