En español | The Supreme Court on June 28 gave the Affordable Care Act a mostly clean bill of health. The court upheld the law's constitutionality, keeping provisions already in effect and allowing other measures to phase in as scheduled.

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On a major new expansion of Medicaid, however, the court gave states the right to opt out without jeopardizing their existing Medicaid programs.

What happens to popular programs already in place and those scheduled for 2014? — Illustration by R. O. Blechman

It wouldn't be easy, but Congress, under prodding from a future president, could change or repeal the law. However, is where things stand now:

How does the law affect my Medicare?

Your guaranteed Medicare benefits are safe, and you can keep your own doctor. Many preventive screenings, including colonoscopies and mammograms, are free. Prescription drugs will cost less as the "doughnut hole," the gap in Medicare Part D coverage, shrinks until it is eliminated in 2020.

Taken together, various measures in the law will save the average Medicare beneficiary $4,181 over 10 years. A beneficiary with high drug costs will save about $16,000.

Some Medicare patients may receive more intensive follow-up care after hospitalization to keep them from being readmitted.

The law changes some payments to doctors, hospitals and other providers. It reduces payments to Medicare Advantage, and some companies offering these plans may charge higher premiums or cut benefits.

High-income beneficiaries will continue to see higher premiums for Medicare Part B and Part D prescription plans.

My employer provides my health coverage. How does the ruling affect me?

If you like your employer's coverage, keep it and do nothing. If you find you can't afford it or you don't like the benefits, in 2014 you'll be able to buy coverage through your state's health insurance exchange, an online marketplace where companies compete for consumers. If you have a low to middle income, you may be eligible for a subsidy to help with the cost. For example, an individual with income of $44,680 now would qualify for a refundable tax credit to purchase insurance on the exchange.

What happens if I don't buy health insurance? Could I go to jail?

Most taxpayers who do not have health insurance by Jan. 1, 2014, will be required to pay a special tax on their returns. If you have Medicare, Medicaid or insurance through your job, you have insurance. Exempt from the tax are people for whom insurance would cost more than 8 percent of their 2014 income and a few other groups. The annual tax in 2014 is the greater of either 1 percent of income or $95. The amount will increase annually in later years. Jail? No, there is no criminal enforcement. But you could lose all or part of a tax refund.

Next: Will you be able to get health care through Medicaid?