The U.S. Supreme Court has upheld the individual insurance mandate for President Obama’s health care law, which clears the way for the next — and most expensive — round of reforms that will be enacted in 2014. The decision will allow millions of people who currently don’t have insurance to get coverage through state exchanges supported by the commercial market place. Those who don’t buy insurance will face a penalty under the law — $95 in 2014 rising to $695 in 2016.

The battle over health care, of course, is far from over. It will now shift to Congress where Republicans will try to repeal the law. In the meantime, businesses will grapple with the increased cost of complying with next round of its provisions. Many companies already have adopted the parts of the law required for 2013, such as extending coverage for dependents through age 25.

Those moves, though, are far less costly than the next batch, which include the coverage for those who currently don’t have insurance or can’t get it because of pre-existing conditions. That one measure alone will inevitably increase premiums for most people who already have insurance.

“It is absolutely an impossible task to manage risk when an individual can enter or leave a commercial product without any restrictions to pre-exisiting conditions,” said Brett Haugh, principal of Houston-based Employee Benefits Solutions, which helps employers manage health-care costs. “That means the price for those products will increase dramatically.”

And that means those costs will be passed on to employers who will either have to bear the cost themselves or pass them on to employees in the form of higher premiums.

Many of the law’s details are still being defined by the Department of Health and Human Services, but the biggest impact is likely to be the cost shift from the new exchanges to employee-sponsored plans, much the way Medicare and private insurers currently shift costs from that program, Haugh said.

“It’s directly tied to opening up millions of people who don’t have insurance today to an insurance product,” Haugh said. He estimates that 40 cents of every health care dollar spent in Houston goes to cover costs shifted from federal programs. When you add millions more people into the system, those costs will go much higher.

“It’s not a long-term solution for the uninsured,” Haugh said.

Shares of health insurers already are falling on the news. UnitedHealth Group fell $1.29, or about 2 percent, to $58 and Aetna dropped $1.17, or 3 percent, to $39.79. That, though, isn’t likely to be a long-term trend. Insurance companies, after all, were deeply involved in writing the law, and they stand to benefit from millions more people buying their products.