Turbotax 2018 Deluxe shows $2400 on Schedule A, line 5a. I entered $3400 in estimated state Income taxes and we don't exceed the $10,000. limit. Why the difference?

posted

Did you make $1,000 worth of estimated state income tax payments for the 4th quarter (which is actually in the calendar year 2019)? If so, those payments would not be deductions for 2018. You can only deduct payments made in the actual tax year (2018). That payment would go on your tax return for next year.