The Supreme Court’s decision to uphold all but one provision in the Affordable Care Act means that for now, at least, one of the most far-reaching overhauls of the nation’s health-care system will be the law of the land. New rules for insurers that have taken effect will remain in place, while new opportunities to gain health-care coverage will begin in 2014.

If I don’t have health insurance, what will happen?

Nothing right away. But beginning in 2014, virtually all Americans will have to obtain coverage or pay a tax penalty. For a single person the penalty will start at $95 per year or up to 1 percent of income, whichever is greater. The penalty becomes progressively larger from 2014 through 2016, when it will reach full strength.

You are exempt from the penalty for certain reasons of financial hardship, such as if the least-expensive plan option in your area exceeds 8 percent of your income.

My employer doesn’t offer insurance and I can’t afford to buy it on my own. What are my options?

Starting in 2014, you will be able to buy private plans through state-based marketplaces known as exchanges. The exchanges are a way for individuals to comparison shop and buy private plans that meet benchmarks for quality.

If your income is low enough, you could qualify for federal subsidies to offset the cost of such a plan. You also may qualify for Medicaid, because the law will expand the program to cover all individuals and families with incomes at or below 133 percent of the federal poverty level. (Depending on location, people with higher incomes may be eligible.)

However, the court said that the federal government cannot force states to comply with the more generous eligibility rules by threatening to take away the federal money they receive for existing Medicaid programs. So it is unclear whether all states will choose to go along with the Medicaid expansion.

I have been refused insurance because I have a preexisting medical condition. How can I obtain coverage?

You may be able to buy it through one of the “high-risk pools” the law has set up in each state, through the end of 2013. But the premiums in the pools vary and can be high.

Starting in 2014, insurers will no longer be able to deny you coverage or charge you higher rates for having a preexisting condition.

I have health insurance. Will my rate go up?

Some of the rules that the law imposes on insurers could contribute to an increase in your premium, although the law has mechanisms to curb big jumps. Your rate may go up for reasons unrelated to the health-care law — for example, if medical costs in your area have increased.

Can my insurance company cancel my plan if I get sick?

No. Your insurer cannot use small technicalities in insurance contracts to cancel your plan if you become ill.

What other rules are already in place?

Insurers can’t discriminate against your children if they have a preexisting condition. They also cannot set a lifetime limit on benefit payouts. Any annual limits will be phased out by 2014.

I lost my job and have insurance through COBRA. What will happen?

Not much will change now. But once the exchanges and subsidies are set up in 2014, they will effectively replace COBRA. So if you leave or lose your job in 2014 or later, you will no longer have the option of staying on your former employer’s plan for up to 18 months. Instead, you will be able to buy coverage through your state’s exchange, possibly with federal assistance.

Can young adult children stay on their parents’ health insurance plans?

If you have adult children, you can put them on your health-care plan until they are 26. The one exception is if your son or daughter already has insurance through an employer, and your plan predates Sept. 23, 2010.

Will my Medicaid benefits change?

For now, your coverage will stay the same. If you are living in a state that was offering Medicaid to a larger share of the poor than required by federal standards, the law has required your state to lock in those more generous eligibility rules through 2014.

At that point, your state leaders will have to decide whether to participate in the law’s expansion of Medicaid. If they choose not to, they could opt to scale back eligibility rules for the program.

Will my Medicare benefits change?

New Medicare benefits under the law remain in effect, including coverage of preventive care without co-pays or other out-of-pocket charges.

The Medicare prescription-drug coverage gap, known as the “doughnut hole,” will continue to be gradually narrowed each year until it is eliminated by 2020. This year, if your drug expenses put you in that gap, drug-makers must give you a 50 percent discount on all brand-name drugs. The government also has begun to provide some relief on generics, covering 14 percent of their cost for those in the gap.

Higher earners will have to pay higher premiums for Medicare Part D (prescription drug) coverage.