You’ve heard of the “fog of war.” Well, now we’ve got the fog of Obamacare. The controversial Affordable Care Act (ACA) has so many moving parts that it’s hard to know how its implementation is proceeding. In 2014, many uninsured are supposed to get coverage either through insurance exchanges, where they can buy subsidized policies if their incomes are less than four times the federal poverty line, or through an expanded Medicaid. The trouble is that 20 or more states may reject the Medicaid expansion, and the exchanges aren’t yet finished. Much is unknown.

It’s not just that the ACA’s plumbing is still under construction. Millions of Americans are perplexed. An April poll by the Kaiser Family Foundation found that one-fifth of respondents didn’t think the ACA was still in force — they thought it had been repealed by Congress or struck down by the Supreme Court. About half the respondents didn’t know how the law affects them personally. President Obama recently called the confusion exaggerated. For the nearly 85 percent of Americans with insurance from large employers or Medicare and Medicaid (programs for the elderly and poor), there would be little change, Obama said.

That’s probably true. But it still leaves a sizable enclave of ignorance — mainly among workers for small and medium-size firms and today’s uninsured. Under the ACA, companies with more than 50 full-time workers are required to provide insurance or pay a fine (now called a tax) of $2,000 per employee (the first 30 are excluded from the tax). Part-time workers, defined as those who work fewer than 30 hours a week, aren’t counted. And uninsured individuals are required to buy insurance or face a tax penalty that begins at $95 in 2014 and increases to $695 in 2016. How will these requirements work? Will smaller companies add insurance or drop it? Will uninsured individuals buy subsidized coverage in the exchanges or pay the tax?

To get some answers, I recently talked with the heads of four “professional employer organizations” (PEOs) — these are companies that act as “human resources” departments for small companies. They provide payroll services and advise on fringe benefits and government regulations. Their customers include construction companies, restaurants, small manufacturers and professional firms. Many of these firms are only now coming to grips with the ACA, because they’d assumed that the Supreme Court would invalidate it or that a Republican White House would repeal it.

To encourage candor, we talked on a not-for-attribution basis. I left with three main takeaways.

First, some companies now providing insurance are being hit with huge premium increases. Before Obamacare, said one PEO adviser, his clients typically received annual increases of 6 percent to 12 percent. “This year we’re seeing 30 percent rate hikes,” he said. The surge is blamed, rightly or wrongly, on the ACA’s requirement for more comprehensive coverage and on its formula for calculating premiums (aka “community rating”). Costlier insurance could cause some employers to drop it and others not to offer it. But modest increases in overall health spending could relieve pressure on premiums.

Second, most companies haven’t made final decisions. Those who have go both ways. Another adviser described a 250-worker car dealership with good wages but no health insurance; it will provide coverage and cut wages to help pay costs. Another example involved a 60-worker manufacturing firm with wages of $12 to $15 an hour. It offered bare-bones policies with steep deductibles. Confronting higher premiums for expanded coverage, the owner will drop insurance. He found the ACA “too complex,” said this adviser. Wages will be increased somewhat. With subsidies, workers might do better in the exchanges.

Third, many firms are revising their business models to minimize insurance costs. One favorite idea: Hold workers below the 30-hour weekly threshold requiring insurance. Many part-time employees who work more (say, 35 hours a week) will lose hours. One adviser discussed a movie-theater chain that will keep most staff below the threshold. Many restaurants and hotels may do likewise. Similarly, companies are striving to stay below the 50-employee ceiling that triggers the insurance mandate. Another adviser mentioned a client, an engineering firm with 48 workers, that had deliberately restrained expansion.

All of this clouds Obamacare’s promise of universal coverage. The Supreme Court’s decision that states don’t have to join the Medicaid expansion will reduce the number who get coverage. What matters for small and medium-size firms is the gap between providing coverage and paying the tax penalties. The wider it gets, the more likely it is that firms won’t provide insurance. Some will also be deterred by the “hassle factor” of complying. The less private coverage, the more federal subsidies for exchanges will rise — and the greater the chances that individual workers will forsake insurance and pay the tax penalty.

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