this is a method that you may want to consider. split your income and deductions.
so the total for both equals the taxable income on the return
take yours and divide by the taxable income.
multiply the fraction from above by the tax before credits.
subtract your share of credits
add your share of additional taxes
subtract your withholding
subtract your share of estimated tax payments
the result could be your share of taxes is actually higher than the amount you paid in
do same for spouse
just to make sure the results for both should equal the refund
basically this is how professional software does it, but judgement is called for in splitting some items such as interest income from a joint account and itemized deductions. professional software will split the items 50/50 when joint is indicated. TT does not have this feature.
