It depends whether you itemize or take the standard deduction.
If you have employee expenses to deduct, you report them on Form 2106, Employee Business Expenses, which you attach to your Form 1040 (when you use TurboTax, we’ll fill in all the right forms for you). The deductible expenses from Form 2106 are entered on your Schedule A, Itemized Deductions.
If you do not itemize your deductions, you cannot deduct unreimbursed employee expenses. In addition, employee expenses are part of the miscellaneous deductions, and subject to a 2 percent floor. This means that only those amounts that are greater than 2 percent of your adjusted gross income can be deducted. For example, if your adjusted gross income is $100,000 and your total miscellaneous deductions are $4,500, you can deduct only $2,500 —2 percent of $100,000 is $2,000, and the amount over that is deductible.
Here's a TurboTax article with more information.
It used to be simpler. Unfortunately, for employees who now telework from home due to COVID, the Tax Cuts and Jobs Act eliminated deductible expenses tied to maintaining a home office )without the need to itemize). Independent contractors (non-employees) may take a home office deduction on Schedule C.
States follow federal guidelines, so what happens on your 1040 flows to your New York tax return. This includes credits and deductions.
