Addl $6k senior deduction

[user17716256448]

On schedule 1A, which calculates the amount you qualify for the additional senior  $12K when both parties are over 65 and filing married filing jointly, it appears the final calculation is based on the individual $6k x 2 vs the $12K.  All dollar amounts that turbo tax uses in the schedule  1A are fro MFJ, but once the phasing calculations are completed, the calculations are subtracted from $6K vs. $12K

As an example, MAGI is $226k for 2 seniors over 65.  Since this  amount is over $150K by $76K x .06 phase out calculations is $4560.  I believe the phased out amount should be subtracted from the $12k max, reducing the the overall senior deduction to $7440.  HOWEVER, Turbo Tax takes the phased amount $4560 from $6k (the per person amount) or $1440 then multiplies x 2 for total deduction of $2880.  The difference in these calculations is $4560 less.  Anybody agree or is TT correct?

[DoninGA]

Look at Lines 36a and 36b.  It is calculating for each person.  The result on Line 37

IRS Schedule 1-A - https://www.irs.gov/pub/irs-pdf/f1040s1a.pdf

[user17716256448]

Thanks for reply. I understand the TT calculation, but my question is why would calculations be  per person, when dollar amounts used to calculate the phased out credit amount are joint numbers, so subtraction should be based on the joint $12k amount, and not the per person amount.  Seems logical to me.  Using the per person calculation reduces the overall credit in my view