But the Kaiser study also found that a relatively small group of households will owe back a lot more than the average when it comes to refunds, after their actual incomes ended up being too high to qualify for the subsidies they got.
That group of people will have an average repayment of between $2,306 and $3,837—and some could owe much more. Unlike people who earn below 400 percent of the federal poverty line, higher earners have no limit on the subsidies they must pay back if they were not entitled to them.
And for low-income subsidy recipients who end up owing money back, the tax bite could strain their already-tight budgets.The average repayment that group of people will have to pay back will be $667, according to the study.
Those who earn less than two times the poverty level are also more likely than other income groups to owe a repayment.
"None of these amounts are insignificant," said Gary Claxton, co-author of the Kaiser analysis, referring to the average amounts all income groups will owe if they face repayments.
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Those average repayments range from $667 for the lowest income group to a high of $1,380 for people just under the 400 percent of poverty level. And the refunds range on average from a low of $412 to a high of $1,601, within the income bands.
And those amounts will come as a surprise to many Obamacare customers, who may not have understood that their subsidies have to be reconciled with their taxes, and as a result will offset the amount of tax refunds they were expecting, or lead to them actually cutting a check to the Internal Revenue Service.
"Some people are not going to know this was coming," Claxton said.
According to a poll Kaiser released last week, 4 out of 10 Americans did not know it was possible that a person who received financial help to pay for their Obamacare plans could end up owing money back to the government.
The new analysis comes less than a month before the April 15 deadlinefor filing income tax returns with the IRS, and after the first year of Obamacare private insurance enrollment.
The study only considered the effects of changes in a household's income. It did not consider changes in household size, which also could affect how much a family will have to repay in subsidies or receive as a refund.