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Level 2
June 3, 2019
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How do I calculate the non-taxable portion of an IRA distribution when part of the IRA funds are pre-tax and part are after tax?

  • June 3, 2019
  • 16 replies
  • 117 views
The IRA was funded with 95% pretax dollars and 5% after tax dollars.  Trying to determine how much of the RMD is non-taxable as a result
    Best answer by AnnetteB6

    If 95% was funded with pretax dollars, then generally 95% of the distribution should be taxable.

    You will not need to do the calculation to determine that amount on your own.  TurboTax will make the calculation based on information that you will enter about your IRA account. 

    When you enter the information that was reported on your Form 1099-R for your distribution from the IRA that includes non-deductible contributions, there will be a series of follow-up questions to answer at the end of that section of the tax return. 

    When you have entered all of the Form 1099-Rs that you received, you will be on the “Your 1099-R Entries” summary screen.  Click Continue to move forward and answer more questions.  These questions will include things such as whether non-deductible contributions were made and tracked in previous years, IRA total basis, the value of all Traditional IRAs, and any other details needed to calculate the taxable amount of the distribution.   

     


    16 replies

    AnnetteB6Answer
    Level 15
    June 3, 2019

    If 95% was funded with pretax dollars, then generally 95% of the distribution should be taxable.

    You will not need to do the calculation to determine that amount on your own.  TurboTax will make the calculation based on information that you will enter about your IRA account. 

    When you enter the information that was reported on your Form 1099-R for your distribution from the IRA that includes non-deductible contributions, there will be a series of follow-up questions to answer at the end of that section of the tax return. 

    When you have entered all of the Form 1099-Rs that you received, you will be on the “Your 1099-R Entries” summary screen.  Click Continue to move forward and answer more questions.  These questions will include things such as whether non-deductible contributions were made and tracked in previous years, IRA total basis, the value of all Traditional IRAs, and any other details needed to calculate the taxable amount of the distribution.   

     


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    roberthgAuthor
    Level 2
    June 3, 2019
    In completing the IRA section I am unable to find the section referred to above that that would generate these follow-on questions.
    Level 2
    April 3, 2020

    Calculation of the non-taxable portion of an IRA distribution due to a basis in the IRA has little bearing upon the percentage of the IRA funding with pre-tax dollars. Form 8606 guides the calculations, and the balance of  unrecovered taxed contributions from the the prior tax year is  applied. Generally, distributions (RMDs and Roth conversions, but not tax-free rollovers)  are added to the year-end value (V) of all IRAs to determine the total value of the IRAs. Subtracting the unrecovered taxed contributions (U) from that total yields the accumulated earnings (A) of your IRAs due to taxed and non-taxed contributions. The ratio of the unrecovered taxed contributions to the accumulated earnings (U/A) establishes the fraction of the earnings due to the taxed contributions. Multiplying that ratio (U/A) times the amount of the distribution (D) determines the non-taxable portion of the distribution.

     

    As an example, consider that your first RMD has occurred, your pre-tax contributions were $95,000 and your after tax (taxed) contributions (U) were $5000. That conforms to your 95% and 5% funding relationship. Further consider that the year-end value (V) of your IRAs happens to be $900,000 and for an age factor of 27.40 applied to the prior year-end value of $880,000 the RMD (D) is $880,000 /27.40 = $32,117. The total value of your IRAs for the year of distribution is V + D = 900,000 +  32,117 = 932,117.  Then accumulated earnings A = V + D - U = 932,117 - 5000 = 927,117.  The ratio of U to A is U/A = 0.0054 (rounded to 4 decimal places). Finally, (U/A) * D = 0.0054 * 32,117 = 173 (rounded to 0 decimal places), and is the untaxed portion of your RMD. The taxable portion then becomes D - (U/A) * D = 32,117 - 173 = 31,944.

     

    It is helpful to understand the underlying calculations when one uses the step-by-step procedures to enter your data.

    Level 15
    April 3, 2020

    "The ratio of the unrecovered taxed contributions to the accumulated earnings (U/A) establishes the fraction of the earnings due to the taxed contributions."

     

    This is correct only if only nondeductible contributions were made.  Regardless, it's a meaningless number with regard to determining the taxable and nontaxable amounts.

     

    "Multiplying that ratio (U/A) times the amount of the distribution (D) determines the non-taxable portion of the distribution."

     

    No, that's wrong.

     

    In your example with $5,000 of basis in nondeductible traditional IRA contributions, a $32,117 distribution during the year and a $900,000 balance at the end of the year, the fraction that is nontaxable is:

     

    $5,000 / ($900,000 + $32,117) = 0.005364

     

    You instead incorrectly calculated that fraction as:

     

    $5,000/ ($900,000 + $32,117 - 5000) = 0.005393

     

    The only reason that these calculations are close is that you used a very large year-end balance.  If the year-end balance was instead $10,000, the correct calculation would produce a nontaxable fraction of:

     

    $5,000 / ($10,000 + $32,117) = 0.1187

     

    while your incorrectly calculated fraction would be:

     

    $5,000/ ($10,000 + $32,117 - 5000) = 0.1347

    Level 2
    April 9, 2020

    There were a few inadvertent errors in my original posting. Here follows the revision:

     

    Calculation of the federal non-taxable portion of an IRA distribution due to a basis in the IRA has little bearing upon the percentage of the IRA funding with pre-tax dollars. Form 8606 guides the calculations, and the balance of  unrecovered taxed contributions from the prior tax year is applied.
     
    Generally, distributions (RMDs and Roth conversions, but not tax-free rollovers) are added to the year-end value (V) of all IRAs to determine the total value (Vt) of the IRAs. Subtracting the unrecovered taxed contributions (U) from that total represents all earnings plus pre-tax contributions (A = Vt - U), that are fully taxable upon distribution.The ratio of the unrecovered taxed contributions U to the total value Vt establishes the fractional part of Vt that U represents. Equivalently, the ratio of A to the total value Vt establishes the fractional part that A, all earnings plus pre-tax contributions, represents.
     
    Multiplying the ratio (U/Vt) times the amount of the distribution (D) determines the non-taxable portion of the distribution that is a partial return of the basis, and the taxable part of the distribution (Dtax) is calculated by subtracting the partial return of the basis from the distribution. For a total distribution, V = 0 and Vt = D, so that (U/Vt) * D = (U/D) * D = U; in other words, the return of your entire remaining basis is untaxed.  If U = 0, you have no basis, the entire distribution is taxed with no need for form 8606.
     
    As an example, consider that your first RMD has occurred, your pre-tax contributions were $95,000 and your after tax (taxed) contributions (U) were $5000. That conforms to your 95% and 5% funding relationship. Further consider that the year-end value (V) of your IRAs happens to be $900,000 and for an age factor of 27.40 applied to the prior year-end value of $880,000 the RMD (D) is $880,000 /27.40 = $32,117. The total value of your IRAs for the year of distribution is Vt = V + D = 900,000 +  32,117 = 932,117. The ratio of U to Vt is U/Vt = 0.0054 (rounded to 4 decimal places). Finally, (U/Vt) * D = 0.0054 * 32,117 = 173 (rounded to 0 decimal places), and is the untaxed portion of the RMD, a partial return of the basis. The taxable portion then becomes D - (U/Vt) * D = 32,117 - 173 = 31,944.
     
    Alternatively for this example, A = Vt -U = 932,117 - 5000 = 927,117 and A/(Vt) = 927,117/932,117 = 0.9946. For D = 32,117, D  *  A/(Vt) = 32117 *  0.9946 = 31,943.5682 which rounds to 31944.
     
    Consider the modified example offered by dmertz, with year-end value at $10,000 but the same distribution of $32,117 and after tax (taxed) contributions of $5000. In this case Vt = V + D = 10,000 + 32,117 and (U/Vt) * D is the nontaxable part of the distribution:
     
    (5,000 / (10,000 + 32,117)) * 32,117
    = (5,000 / 42,117) * 32,117
    = 0.1187 * 32,117 = 3812 (rounded)
     
    So the taxable part is $32,117 - $3,812 = $28,305
     
    Using the alternative approach of A = V + D - U = Vt - U = 42,117 -5,000 = 37,117, then (A/Vt) * D yields directly the taxable part of the distribution:
     
    (37,117 / 42,117) * 32,117
    = 0.8813 * 32,117 = 28,305
     
    and the non-taxable part is the difference of the taxable part from the value of the distribution:
     
    $32,117 - $28,305 = $3,812
     
    Note 1:
    Form 8606 has line-by-line entry for all of the data with D provided as total ordinary IRA distributions (Dord) and total Roth conversion distributions (Drc) on separate lines (line 7 and line 8). The fraction U/Vt (line 10) is multiplied times each of those two distribution values and the resulting values of untaxed portions placed on  lines 11 and 12. The sum of the two values of untaxed portions is entered on line 13, which represents the basis change for the current tax year, and is used in the calculation of the remaining basis applicable to the next tax year.
     
    Note 2:
    In case non-deductable contributions are made during the current tax year and for the current tax year during 1/1 through 4/15 of the following calendar year, Form 8606 determines the basis through the year end of the current for calculations of taxable and non-taxable portions of IRA distributions.