The next example I am going over is, family filing jointly making 165k with 2 children. Tax Foundation says after the tax cuts expire they would owe $2450.50 more. A “custom” tax situation with their calculator and putting in the same details again I get an increase in taxes by $5541.50. Doing the math myself I get a tax burden increase of $4259.94 (without factoring the child tax credit to boot!).