SACRAMENTO, Calif. – As the nation heads into the second year of the health care law, the federal government and states are preparing for open enrollment. Starting Saturday, consumers will be able to enroll for 2015 coverage through health insurance marketplaces, also known as exchanges. The marketplaces in each state will allow you to shop for plans and apply for tax credits that can greatly reduce your premiums. You can also find out if you qualify for free or low-cost coverage through Medicaid.

Here are some changes for 2015:

Q: What is happening with health plan costs and how much will I pay?

A: Plans and premiums for 2015 are now online at HealthCare.gov or your state’s exchange. You can apply between Nov. 15, 2014, and Feb. 15, 2015. Plans cover essential health benefits, pre-existing conditions, and preventive care. If you were already covered this year, you can change plans during open enrollment.

According to PricewaterhouseCoopers’s Health Research Institute, the average premium will be around $344 before tax credit subsidies. That’s an increase from 2014 of about 3.5 percent. Premiums vary from state to state with some down as much as 22 percent and others up 35 percent.

The good news is that most people who apply through exchanges will qualify for tax credits that reduce their premiums. For 2015, individuals earning between $11,670 and $46,680 qualify for a premium tax credit. For a family of four, the range is $23,850 to $95,400.

Q: What should I have ready when applying?

A: If you had coverage in 2014, it’s helpful to take stock of what’s changed and include any changes you expect in 2015 including: income changes, births, deaths, marriage or divorce, anyone in the family who got coverage through a job, anybody getting health coverage through a public program like Medicare or Medicaid.

Q: What other out-of-pocket costs should I consider?

A: The maximum out-of-pocket cost for any marketplace plan for 2015 can be no more than $6,600 for an individual plan and $13,200 for a family plan. This is the most you pay a year before your health insurance or plan starts to pay 100 percent for covered essential health benefits.

This limit includes deductibles, coinsurance, copayments or any other qualified medical expense. It does not have to count premiums, out-of-network costs or non-essential health benefits.

Q: Will I get to keep my doctor?

A: Check with your insurance company to make sure your doctor will still be in the plan’s network in 2015. Exchange websites will route you to the health insurance company’s online list of doctors. You also can contact your doctors directly to see which health plans they will accept in 2015.

Q: What if I don’t buy health insurance?

A: The penalty is going up for people who go without health insurance. It’s at least $325 per adult, or 2 percent of income, whichever is greater, up to a cap.

Q: If I signed up for insurance through the exchange last time, do I have to go through that again?

A: No, but that might not be wise. If you do nothing, you will be automatically renewed in your current plan on Jan. 1. But you’ll be getting last year’s tax credit, which could well be lower than the amount you’re entitled to for 2015. And there are lots of new plans available, so you may also miss out on a lower-cost option. Officials are advising existing customers to go back to HealthCare.gov or their state exchange, update their financial and household information, and at least check other plans. If you want to make any changes, you’ll have to do that by Dec. 15 to avoid a break in coverage on Jan. 1.

If you live in a state that is running its own exchange, the rules for automatic renewal may be different.

Q: How will my premium tax credits impact my taxes?

A: The vast majority of current customers are getting tax credits to help with premiums. Those subsidies are tied to income, so you’ll have to account for them when you file your 2014 taxes. HealthCare.gov or your state’s exchange will send you a form in January that reports how much you got. You’ll use that information on a new tax form to be filed with your 2014 tax return, to prove you got the right amount of tax credits. Too much subsidy and your tax refund will get dinged. Too little, and the government owes you. It’s bound to cause anxiety because many people depend on their tax refunds to pay bills.

Q: What happens to me if I got an extension under President Barack Obama’s decision to allow people to keep plans slated for cancellation last year?

A: Some plans that existed before the health care law passed do not include new benefits and protections. They are not offered by exchanges. Some of them are being changed by insurers to incorporate new benefit requirements, some are being canceled and some states are allowing people to renew their plans through 2016.