Federal income taxes owed and paid for a prior year are not deductible.
State income taxes owed and paid for a prior year are deductible on your federal return (you can only claim the actual taxes paid, you cannot claim any penalty or interest).
For state income taxes paid:
- Federal Taxes (Personal for Home & Business or Self-Employed)
- Deductions and Credits
- I’ll choose what I work
- Scroll down to Estimates and Other Taxes Paid
- Other Income Taxes – click Start or Update
- Scroll down to Other Income Taxes Paid in 2015
- Click Start on the taxes you paid