You have to make estimated Ohio income tax payments for the next year only if the sum of (i) your previous year overpayment credited to current year (see line 26 on page 2 of form IT 1040) and (ii) your current year Ohio income tax withholdings is not equal to or greater than either of the following:
- 100% of the previous year Ohio income tax (see page 2 of Ohio form IT 1040: line 17 minus line 24); OR
- 90% of the current year tax.
For purposes of these tests, you must reduce your previous overpayment credited to your current year 2010 by any year 2009 tax payment that you made after April 15.
If you do not meet either of the tests above, you must timely pay enough estimated Ohio income tax so that the sum of (i) your prior year overpayment credited to your current year, (ii) your current year withholdings and (iii) your timely made estimated Ohio income tax payments is not less than either of the two tests above.
If you are required to make estimated payments and do not, you may be subject to an interest penalty on your underpayment of estimated taxes.