If your interest is exempt from New York only:
The amount you enter in Box 3 will be added to the total interest income on the federal return, and will be entered on New York Form IT-201, Line 28 or Form IT-203, Line 27.
If the interest is exempt from Federal only OR both Federal AND New York:
You have $2,000 dollars of total interest, with $1,000 being federally exempt and $300 being New York State exempt. Enter $1000 in Box 1 of the Form 1099-INT Interest Income. The $1000 that is federally exempt would be entered in Box 8. The $300 that is exempt from New York State taxes would be entered as the "Amount from Box 8 that is both Federal and State exempt interest."
In this example, the following interest income would be reported on the federal and New York State returns:
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