Why did my income tax due rise from ZERO to over $1,000 in 2016?

[Lisa995]

Nobody here can see your returns or your information.  The easiest way to tell is to compare each years return side by side against the other...where do the differences appear?

[SweetieJean]

Did any of your dependents turn age 17?  If so, you lost their Child Tax Credit.

[SweetieJean]

Your other post referred to State tax. Which state?  Your state may have changed its tax law.

[SweetieJean · Accepted solution]

Lisa's suggestion above is a good one. Also check for data entry errors, such as a missing or misplaced decimal point, or extra zeroes at the end of a number.