The deduction for state and local taxes is generally limited to $10,000 ($5,000 if married filing separately).
Generally, you can deduct on Schedule A (Form 1040) only the amount of your medical and dental expenses that is more than 7.5% of your AGI.
80 percent of the amount of the itemized deductions otherwise allowable for such taxable year. ½ the amount applicable under subparagraph (A) (after adjustment, if any, under paragraph (2)) in the case of a married individual filing a separate return.
Overall limit As an individual, your deduction of state and local income, general sales, and property taxes is limited to a combined total deduction of $10,000 ($5,000 if married filing separately). You may be subject to a limit on some of your other itemized deductions also.