The number of uninsured Americans is about 45 million and climbing. Companies like General Motors, with large numbers of older or retired workers receiving generous benefits, are struggling under ever-higher health care bills. More companies are abandoning their role in providing health insurance to their employees, and some people worry the federal tax overhaul now being discussed could scare away even more employers. 

So, are we in the final days of the company health plan? Probably not. 
Frustrations with the status quo notwithstanding, the current system of providing insurance to most working Americans through their employers is not likely to disappear, according to policy analysts and consultants in Washington and around the country. That is mainly, they say, because none of the other possibilities, like a government-run plan or some new private-sector solution, have enough support to serve as a replacement. 

Employers "are not about to get out of the business of providing health insurance to employees, even though they complain so loudly about it," said Paul B. Ginsburg, the president of the Center for Studying Health System Change, an independent research group in Washington. 

Inspiring the latest round of debate is the proposal introduced last month by the President's Advisory Panel on Federal Tax Reform, as part of a sweeping effort to overhaul the tax system. Under the proposal, tax breaks for both employers and their workers for health benefits are limited to $11,500 of coverage for a family and $5,000 for an individual. Under current tax law, there are no limits to how much coverage is exempt from payroll and income taxes. 

Many say the proposal is a political nonstarter. But some critics see it as a threat to a system that is already unraveling. Only 60 percent of employers now offer coverage, compared with 66 percent as recently as 2003, according to annual survey conducted by the Kaiser Family Foundation, a nonprofit health research group in Menlo Park, Calif. In 2000, the percentage was 69 percent. If the tax advisory panel's recommendations on employer-sponsored health care went into effect, they would "dismantle our current health care system," Representative Pete Stark, a California Democrat, said in a news release.

That might be an exaggeration, and the proponents of the plan assert that they are not trying to take away the entire tax advantage of providing employer-based coverage. Instead, people may view it as "a tax on excessive health plans," one of the panel members, Representative Connie Mack, Republican of Florida, said in a news conference. 

But employers, particularly large companies that have long offered generous benefits to employees as part of their compensation, are also watching carefully, consultants say. "It raises a lot of concern among employers who currently offer health care coverage," said Frank McArdle, the manager of the Washington research office of Hewitt Associates, a human resources consulting firm. 

While the average current plan is not generous enough to be taxed under the proposal, consultants say the high rate of health-care inflation could push many plans past that limit and create a problem for employers in the future.

Companies are also worried about more talk in Congress of making health benefits count toward income subject to Social Security taxes. "That's enormous for employers," said Gretchen Young, an executive with Aon Consulting, which advises companies on benefits.

Still, the political odds are against any major tax reforms occurring anytime soon. The debate over the fairness of the current tax system, which benefits employees with rich coverage more than people who must buy health insurance on their own, is not a new one. Neither is the heated argument over how best to deliver health care in this country. 

The proposals "are beloved by policy wonks," said Helen Darling, the president of the National Business Group on Health, a coalition of employers. "They have been debating them and pushing them for 30 years." 

Which is not to say that employees or employers are satisfied with the current state of affairs. Employers increasingly worry about their ability, and the ability of their employees, to pay for care. But they also recognize that the growing numbers of people without insurance only add to their own health care bills, by expanding the numbers of people without coverage who show up in emergency rooms and contribute to the overall rise in health care costs. "There's a higher level of frustration, and there's a greater desire for solutions," Ms. Darling said.
 
What is also clear, though, is that there are no clear alternatives. Corporate executives and many others are leery of a government solution, but no one has come up with a private-sector option that has gained significant support. Because individuals who buy private insurance on their own pay much higher prices than the group rates employers get, many people could probably not afford health insurance if their employers were not buying it for them. 

"There's no functioning individual market" for insurance, Ms. Darling said. 

Employers are experimenting with ways that shift more of the additional costs onto their workers while providing incentives to them to pay closer attention to the cost of insurance and their own care. But at least one of these tools, health savings accounts, would be eliminated under the tax advisory panel's plan. The proposal favors a broader savings vehicle, paid through after-tax dollars, that could be used by families for more than health care expenses. 

So far, at least, many large companies that offer health benefits cannot risk stopping because they need to compete for workers, said William Custer, an associate professor of risk management and insurance at Georgia State University's Robinson College of Business. "As much as many employers bemoan the rising costs," he said, "they can't move by themselves without endangering their position in the labor force." 

And while change may be inevitable at some point, no one is willing to predict how soon a sufficient consensus might emerge to allow something significantly different than the current system. "We've been teetering towards a crisis for a long time now," Mr. Custer said.