Tax filers, confused over Obamacare, flock to pros: CEO

H&R Block is seeing a surge in business as more Americans struggle with tax issues related to the Affordable Care Act, CEO William Cobb told CNBC on Monday.

Americans who are in health-care exchanges are confused because they have to reconcile costs and tax credits depending on their final income for the year, he said in a "Squawk on the Street" interview. Others must determine whether they are eligible to be exempt from penalties after going without coverage.

"Because of additional forms and this reconciliation to the actual income, it's millions more, and we're seeing that in the amount of people coming into our offices now," he said.

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The government now estimates 3 million to 6 million Americans will pay a tax penalty related to the health-care law, Cobb said. An addition 20 million or so are seeking an exemption.

Cobb does not expect a significant uptick in auditing activity because the government mandate that all Americans purchase some form of health care under the ACA is fairly clear cut from an auditor's perspective. "You either have insurance or you don't, because it's the law of the land."

H&R Block is still determining whether new business related to health-care inquiries will provide higher margins than the traditional preparation services it has provided in the past.

Tax preparation firms have faced the prospect of lost revenues for years as more Americans turn to free online tax preparation services.

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"We have to see how this plays out," he said. "I've told our analysts and the investors this is going to play out over a couple of years, and we don't have to have a good quantification yet because it's still early. Tax season is just kicking off."

The firm has also tried to attract customers by recasting tax season as refund season in a series of advertisements that play up how much money do-it-yourself filers leave on the table by forgoing professional advice.

"People love the ads and it's really drawing people in," he said.