Sunday, Feb. 15, is the last day consumers can enroll in Obamacare health coverage if they want their plans to become effective by March 1, 2015. Nearly 1.4 million Americans have enrolled in new plans through the federal exchange since open enrollment began in November, according to the Department of Health and Human Services. 

As new insurers plan to enter (and, in some cases, leave) the marketplace while others tweak their benefit offerings for 2015, now is the time for consumers to review their plans to make sure they’re properly covered.

Whether you’re already enrolled in an Obamacare plan or decided to take a pass on insurance coverage this year, the following tips will help guide you through the enrollment process.

“You’ve got to shop around,” says Jennifer Sullivan, director of the Best Practices Institute for Enroll America, a nonprofit that helps consumers sign up for health coverage. “Even if you want to stay in your plan, you still have to go back to the marketplace and update your information.”

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1. Check your mail.

Everyone who signed up for a plan through the federal marketplace or their state’s exchange in 2014 should have received two letters by now — one from their insurer and one from the marketplace itself — reminding you about open enrollment. The letter from your insurer is arguably the more important of the two, because that’s where you’ll find out whether your insurer plans to keep your existing plan or change it in 2015.

2. Log on to the health care marketplace.

 Even before open enrollment opens on Nov. 15, you should log into your Healthcare.gov (or state marketplace) account to be sure you are able to register. For security purposes, the websites ask users to change their passwords frequently, which means you might have to come up with a new one before you can even log into your account. If you didn’t sign up for coverage in 2014, just create a new account on the federal marketplace or via your state exchange.

3. Update your personal information (household size, income, ZIP code, etc.).

Even a small change in your income could be important because it factors heavily into your eligibility for a tax subsidy. Eighty-five percent of Obamacare enrollees in 2014 received tax credits that lowered their premiums, according to the Congressional Budget Office. Also, major life changes like a new marriage, divorce, having a new child, or a dependent moving out of the house can impact the size of your tax credit -- and as a result, the cost of your plan.

4. Figure out what tax credit you qualify for.

Because the maximum tax credit available to Obamacare enrollees is based on the cost of the second-lowest priced silver plan (referred to as the “benchmark silver plan”) in each state, your tax credit might change in 2015. Premiums for the benchmark silver plan haven’t changed all that drastically on the whole (on average, the benchmark plan price fell by 0.2% in 48 states, according to the Kaiser Family Foundation). But in some states, the average premium has changed quite drastically. For example, in 2015 the average cost for a benchmark silver plan will be 10% cheaper in Arizona, which means people in that state may wind up getting a smaller tax credit than they did in 2014. Don’t let all the math confuse you, though. You can get an easy estimate of your tax subsidy by going directly to Healthcare.gov and entering a few pieces of information, or by using the health care plan estimation tool on Kaiser Family Foundation’s website.

5. Time to comparison shop.

Even if you absolutely love the plan you had in 2014, it’s worth shopping around to see if the rates or the coverage are going to change next year. It’s also possible that your insurer could change specific benefits within your plan, like its coverage of certain drugs and treatments and the network of doctors and hospitals available to you. After test driving a high-deductible health plan in 2014, you might have realized you’re not comfortable with such a high out-of-pocket expense. Now’s your chance to sign up for a plan that better fits your budget. Insurance companies frequently change the rates and coverage options of their plans. According to Enroll America, there will be 25% more insurance plan options in 2015 than there were on the exchange in 2014.

6. Don’t be afraid to ask for help.

There’s no question that signing up for coverage through the marketplace last year was a bit of a debacle. The site is under new leadership this year and has been undergoing tests to ensure it will be able to withstand heavy traffic as open enrollment begins. If you run into any issues, however, help is easier than ever to find: call the Marketplace Hot line (1-800-318-2596) and speak with a staffer who can help you pick a plan or review your existing benefits over the phone. Or find a health care navigator (someone who’s been trained to help consumers sign up for coverage) by entering your ZIP code here. (If your state has its own exchange, like New York or California, visit their website to find a navigator). Consumer groups like Enroll America also have experts on hand to help across the U.S.

7. Keep important dates in mind.

Keep in mind that the open enrollment season is only three months long this year, compared to last year’s six-month window. You have until Dec. 15 to sign up for a plan if you want to have coverage beginning Jan. 1, 2015. If you sign up after Jan. 1, your coverage will begin on Feb. 1, which means you might have a gap in coverage for the month of January. The final deadline for enrollment is Feb. 15, with new coverage beginning March 1.  

8. If you don’t change or renew your plan, prepare to get auto-enrolled.

You won’t be alone. In a recent survey, the Kaiser Family Foundation found a whopping 90% of uninsured people in the U.S. didn’t even know when open enrollment for the federal marketplace started. The good news is that the bright folks behind the new health care exchange included an auto-enrollment feature. In most states if you do nothing, you’ll automatically be enrolled in whatever plan you had in 2014. However, if your insurer has adjusted your benefits or the cost of your premium, you could be in for an unwelcome surprise when you start getting your monthly premium bills in the new year. Also, if your insurer happens to have gotten rid of your particular benefit plan in 2015, they will shift you into another plan they deem most similar to the one you had in 2014. That’s why it’s so important to check out the marketplace and see what will change in 2015.

9. If you go without insurance, know what to expect.

More than 8 million people have signed up for new health plan under the Affordable Care Act, but millions more have decided to go without insurance. Depending on your circumstances, you might qualify for an exemption that will save you from getting hit with tax penalties for not having health coverage. For example, if the cheapest plans available in your state cost more than 8% of your household income, or you didn’t earn enough to file a tax return for 2014, you should be exempt. If none of these exemptions apply to you, get ready to pay up. The penalty for not having insurance in 2014 is $95 per adult or 1% of your household income, whichever is greater. And that goes up in 2015 — to $325 per adult or 2% of your household income.

[This post has been updated from an earlier version]

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