The 2014 income tax season, the first since the Affordable Care Act became law, proved to be a bumpy ride for many people who received government help to pay for health insurance. One major tax service reported that 61 percent of its clients who used the federal subsidy in 2014 saw their tax refunds reduced by an average of $729, because they underestimated their expected 2014 income.

Under ACA, those with expected income below a certain level can qualify for the health insurance credits. That income is verified later when they file 1040 forms. If you made more or less than expected, the credit is adjusted.

Jennifer Konvalin, Rapid City CPA and Ketel Thorstenson partner, said she wasn’t surprised by the report. For one thing, she said, a lot of people don’t realize that gross income, from which the credit is calculated, is different than take-home pay.

Also, Konvalin added, some people have widely fluctuating income. “For somebody who is a W-2 employee, income may not change significantly from year to year, but for farmer-ranchers and the self-employed, income can fluctuate a lot,” she said.

In one recent case, she helped a client reduce his adjusted gross income by putting money into a retirement account and a health savings account. He avoided repaying thousands of dollars in health insurance credits. Another client didn’t have enough income to qualify. She tried to help him find ways to increase his reported income in order to qualify.

Another couple she worked with this tax season had decided a year ago not to buy insurance through an exchange, because they feared they might have to pay back the difference. It turned out they would have qualified, but only if they had purchased insurance through an exchange.

This year, she suggested, they could look at buying through an exchange. If they earn too much, they might have to return some money – but could end up paying about the same as private insurance if they found a similar cost plan. If they qualify for the credit, they would save a lot next year.