What we know: The Affordable Care Act, popularly known as Obamacare, required everyone to have health insurance beginning in 2014. If you didn’t get insurance and didn’t qualify for an exemption, a penalty of $95 or 1 percent of your income, whichever is larger, will be added to your 2014 tax bill. To provide financial assistance to Americans who could not otherwise afford health coverage, the law made payment of federal premium tax credits, or subsidies, available to eligible individuals who purchased health coverage through exchanges, or marketplaces.

What we are learning: Many policyholders who received a subsidy in 2014 face uncertainty about their tax bills. Some have happily uncovered surprise refunds while others had higher-than-expected tax payments. This is because the subsidies are only an estimate and must be reconciled based on actual income and family status when people file their taxes.

Those who chose to take less than their allowed premium subsidy per month or received an underpayment of the tax credit, may get a refund after reconciling the subsidies received with their actual annual income. However, many Obamacare policyholders would not have been able to pay their insurance premiums if they didn’t take their full subsidy each month. These policyholders as well as those who received an overpayment of their premium tax credit may have to repay that, in whole or in part, when they file their taxes. This repayment obligation may be because of an unexpected midyear increase in income or as a result of getting married.

What should you do? Obamacare policyholders should report any change in income or family status to HealthCare.gov right away. This insures your subsidy is adjusted immediately and will prevent surprises when filing your taxes.

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