Most people try to get through open enrollment without changing a thing. But that inertia might cost them hundreds of dollars later.

Even people who haven’t seen a change in their jobs, health or coverage may have to pay more next year than they did this year. That’s because they could be passing up on a new plan that might be a better fit. And with more insurance companies taking part in the public insurance exchanges this year, some people might find they’ll get a smaller subsidy — even if their plan stayed the same.

“Last year we focused so much on just understanding the Affordable Care Act,” says Carrie McLean, director of customer care at eHealthInsurance, an online insurance broker. “This year is really about picking the right plan.”

It’s complicated stuff. Oddly enough, people who make a decision based just on price may end up paying more than they need to. Whether you’re comparing the options offered through your job or shopping on the exchanges, here are some steps to keep you from ending up in the wrong plan this open enrollment season.

1. Reapply if you’re buying on the exchanges. Many people who bought insurance on ACA exchanges last year will be automatically enrolled into those plans for next year. But that doesn’t mean their costs won’t change. People who changed jobs, got a raise or aren’t making as much as they did last year should update their information on the exchanges to make sure their subsidy isn’t too big or too small. Workers who can get affordable coverage through their jobs won’t qualify for subsidies, even if they meet the income requirements. (Generally, subsidies are available to people earning between the poverty level and four times the poverty level.)

Some people might be missing out on more than just the subsidy — they might be limiting their plan options altogether. People who make below 250 percent of the poverty level can access plans with lower deductibles and copayments, says Karen Pollitz, a senior fellow for the Kaiser Family Foundation. If their income isn’t updated in the system, those plans may not come up when they search on the exchanges, she says.

2. Watch out for price changes. Premiums aren’t expected to increase by much, overall, this year. But some local markets may see big jumps, or drops, in price as more insurance companies enter the exchanges, McLean says. Those who don’t shop around could be passing up a better deal, she says. People receiving federal subsidies might also have to pay more for their plans — even if those plans cost the same and if they’re making the same as they did last year.

As my colleague Jason Millman reported, that’s because some areas will see a change in what’s known as the “benchmark” plan, or the second lowest cost silver plan on which subsidies are based. If the benchmark status goes to a cheaper plan, some people in that market may find their subsidies won’t go as far as they did last year, even if their plans stayed the same.

3. Double check that your doctor and drugs are covered. Some people chose plans last year based on price only to find out later that the doctors or the medications they need are not included, McLean says. Any savings they made by choosing plans with lower premiums were likely erased when they got bills for doctors’ visits or prescriptions that weren’t covered, she says. Some 23 percent of eHealth customers surveyed this summer said they plan to avoid making that same mistake this year.

eHealth has a tool that lets people search a doctor’s name to see which plans include that doctor in the network (though not all exchange plans will be included). Insurance companies also offer information on their Web sites about which doctors, hospitals and drugs are covered by specific plans. When it comes to drugs, people should check what tier a medication is in for the plan they’re considering, says John Barkett, director of health policy affairs for Towers Watson, a human resources consulting firm. Generally, a tier 1 drug (usually a generic) will be cheapest while a tier 3 drug (typically brand name) will be most expensive.

4. Start early. Most people procrastinate when it comes to anything related to money. But you don’t have as much time to choose a plan this year as you did last year. The open enrollment period for the exchanges, which starts Nov. 15 and ends Feb. 15, is half as long as it was last year. Those who want to be covered by Jan. 1 need to decide by Dec. 15.

People should start shopping sooner rather than later so that they can give themselves time to deal with any technical glitches and to properly compare plans, says Dan Mendelson, chief executive of Avalere Health. The same goes for people who are comparing plans offered through their jobs, where they might only have a few weeks to make a change. “You don’t want to get jammed on this,” he says.

5. Re-evaluate family coverage. As much as you would like to avoid it, now is the time to make sure your family is signed up in the most affordable plan. Some employers are making it more expensive to include a spouse or child, so you may find it’s cheaper to move the children over to your partner’s plan. Some families may even find that it’s less expensive to move part of the family on to plan purchased through the exchanges, says Carolyn McClanahan, founder of Life Planning Partners. (They probably won’t qualify for a subsidy, however, if they can be added to an employer-provided plan.)

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