Where does the value in line 16 (Tax) in Form 1040 come from?

Hi guys,

I’m starting my 2023 tax returns, and although my taxable income in 2023 is slightly less than in 2022, I owe taxes this year, whereas I received a refund last year. I’m trying to figure out what changed. I have two sources of income: one variable and one stable. The variable income changed by less than $1,000. Any advice would be appreciated.

EDIT: I understand now that Line 16 comes from the tax tables. It looks like the difference in my taxes this year is due to some taxes on Line 23 that I need to figure out.

EDIT 2: I used a W-2 parser for the first time instead of manual entry. It misread my Box 12 “W” as “N,” which created this extra tax on Line 23. A very silly mistake…thanks to everyone who took the time to answer. I still learned a bit more about the 1040 than I knew previously.

The value on line 16 (Tax) of Form 1040 comes from the tax table or tax computation worksheet, which is based on the taxable income reported on line 15. When using a program like TurboTax, the software automatically calculates and fills in this amount based on your inputs during the interview process.

The value in line 16 of Form 1040, which represents the total tax I owe, comes directly from the IRS Tax Tables based on my taxable income reported on line 15. Essentially, I look up my taxable income in these tables to find the corresponding tax amount. This figure reflects the total tax before considering any payments I’ve already made through paycheck withholding or estimated tax payments. If I have additional factors like qualified dividends or capital gains, I might need to use specific worksheets to calculate my tax more accurately. Understanding this process helps me ensure that I accurately report my tax liability and avoid any surprises when filing my return.

Your total tax liability, as calculated by the tax table, is found on line 16. This amount doesn’t include taxes already paid.