Gov (search: IT-2104-I) or scan the QR code below. IT-2104. The goal is to not under or over withhold income taxes from your employee wages in New York State, New York City, and Yonkers.Complete Form IT-2104 each year and file it with your employer if the number of allowances you may claim is different from federal Form W-4 or has changed. Today we are talking all about the new york state withholding form and how to fill that out. Use the New York State Form IT2104, which employees fill out, to determine the correct withholding amount. Employers have to fill out only Form NYS45, Quarterly Combined Withholding, Wage Reporting, and Unemployment Insurance Return. Use the New York State Form IT2104, which employees fill out, to determine the correct withholding amount. Employers have to fill out only Form NYS45, Quarterly Combined Withholding, Wage Reporting, and Unemployment Insurance Return. Every employee is required to complete a federal Withholding Allowance Certificate (W-4), which can also be utilized for state and local withholdings. You must give Form NJ-W4 to your employees to fill out and return to you.