That's not to say that low- and middle-income households don't benefit from the major tax breaks and wouldn't notice if they were curtailed -- a distinct possibility when lawmakers eventually do embark on tax reform.
This year, households in the middle income quintile will enjoy about 13% of the value of the biggest breaks, the budget office estimates. Those in the middle include one-person households earning roughly $39,000 to $55,000 and four-person households earning between $77,000 and $110,000.
The lowest earners, who make no more than $25,000 as singles or $50,000 as four-person households, will get only 8% of the benefit of the tax expenditures. What value they do see will come primarily from the Earned Income Tax Credit and, to a lesser extent, the child tax credit.
"Those credits are expected to be substantial," the CBO wrote. At the same time, it also noted that "because many of the lowest-income taxpayers will be eligible for Medicaid, they will not benefit from the tax expenditure."