A married couple with an adjusted gross income in 2013 of $40,000 pays $5,107.50 in income taxes, factoring in a 10 percent rate on the first $17,850 and 15 percent on the last $22,150. In 2013, the Bush-era tax cuts were extended for all taxpayers excluding the highest tax bracket.
Singles making $40,000 a year are taxed at a 25 percent tax rate while those married filing jointly and head-of-households filers making the same amount are taxed at a rate of 15 percent. The effective income tax rate is 12.8 percent for the married couple, dividing $5,107.50 by $40,000.00. This does not take into consideration any tax credits or other factors besides income.