IRS 1040 line 16 tax calculation-different calculations from TurboTax, H&R, and IRS tax computation sheet

[AbTrack]

I have entered the same income values in both 2024 TurboTax Premier and H&R Premium software with the result that line 15 of the 1040 is the same number in both software. However, they calculate different line 16 Tax values.

I then tried entering the same line 15 value into the IRS tax computation worksheet (Section B for married filing jointly), and I get a Tax value that is different from TurboTax and H&R. So, 3 different line 16 values.

Any clues to what might be going on?

[VolvoGirl]

You probably missed entering box 1b or 2a  on a 1099DIV on one of them.  

There are like 7 different ways to calculate the tax.
It's very common for the tax to be less than you can figure using the IRS tables. It depends what kind of income you have. Even though the full amount shows up in the total income on the 1040 line 7, if you have capital gains or qualified dividends the tax is not taken from the tax table but is calculated separately from Schedule D. The tax will be calculated on the Qualified Dividends and Capital Gain Tax Worksheet. It does not get filed with your return. In the online version you need to save your return as a pdf file and include all the worksheets to see it.

For the Desktop version you can switch to Forms Mode and open the worksheet to see it. Click Forms in the upper right (upper left for Mac) and look through the list and open the Qualified Dividends and Capital Gain Tax Worksheet. And you will need to use this IRS worksheet on page 15.
https://www.irs.gov/pub/irs-pdf/i1040tt.pdf

IRS Qualified Dividends and Capital Gain Tax Worksheet—Line 16 on 1040 instructions page 37
https://www.irs.gov/pub/irs-pdf/i1040gi.pdf

[AbTrack]

Thanks for the quick answer. It all came down to I missed inputting a 1b qualified dividend. But your suggestions helped me trace it.