In general, individual taxpayers are considered to be on a "cash basis" in that you report income received in that tax year and expenses (property taxes, etc) that were paid in that tax year. You should enter your STAR exemption as the amount that your received in 2023.
From the instruction to Form IT-214:
Line 23 Homeowners: Enter any real property taxes paid for your residence by you or your spouse during 2023 to a county, city, town, village, or school district. If your residence is on more than one acre of land, only enter the amount of taxes paid on the residence and the one acre of land around it. See the definition of residence above. In computing the amount of taxes paid, you must reduce taxes paid by any School Tax Relief (STAR) credit (Tax Law section 606(eee)).
Click here for instructions for Form IT-214.
Click here for information on New York State's Real Property Tax Credit.
Click here for additional information on real estate property taxes.
Click here for information on the cash basis for accounting.
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