Get your taxes done using TurboTax

First, you can look to see exactly what computation method TurboTax used to figure your tax.  Here's how:

Assuming you are able to see all the forms of your return, look at a worksheet called Form 1040 Worksheet (may be abbreviated as "1040 Wks" in the forms list).   On that worksheet,  scroll down between Lines 15 and 16, and there is a large box called "Tax Smart Worksheet."   It will show you the method that TurboTax used to calculate your taxes.   As an example, if someone had any capital gains/qualified dividends, it will first use the "Qualified Dividends and Capital Gains Worksheet."   There are other possible tax calculation worksheets that can be brought into play depending on the items in one's return.   But you will see there which one (or possibly more) was used.

If your income is simple and straightforward without requiring additional special calculation worksheets, since your income was over $100,000, it likely used the "2023 Tax Computation Worksheet."    If that's what is displayed as the method in the "Tax Smart Worksheet" mentioned above, below is an image from that worksheet.

Are you filing as "married filing jointly?"   When I chose that filing status and plugged in your numbers, I also got the $15,900 figure, but please verify for yourself by doing the computation shown in the image.  It is a two-step computation.  The top note in the image is for folks who had any of those other additional computation worksheets.   Click image to enlarge.

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