Open enrollment is a special, select period of time when you can buy, change, or cancel your health insurance coverage. It’s important to pay attention to when open enrollment begins and ends for your insurance plan — it isn’t the same set of days every year, like a Christmas or Thanksgiving holiday.

Open enrollment will vary by plan and by state; some types of insurance don’t even have open enrollment periods.

For most insurance plans, open enrollment occurs in the fall, with coverage to begin on Jan. 1 of the next calendar year.

What is open enrollment?

When you purchase health insurance, you buy a level of coverage (known as a plan) for the entire year. It isn’t a month-to-month subscription, and you can’t change your coverage in the winter for flu season or if you’re expecting an expensive surgery in the fall. Because insurance hedges against risk, you can’t raise or lower coverage on a whim, which is why open enrollment exists.

It’s critical that you not miss your open enrollment period because it’s the only time you can make changes, often called elections. Generally, you can’t make any other changes to your plan during the year — although there are some exceptions.

Insurance plans that participate in open enrollment season every year include:

• Plans purchased through the Affordable Care Act (ACA) marketplace

• Medicare

• Medicare Advantage

• Employer-sponsored health plans

Learn More: Compare Medicare Quotes

When does open enrollment begin?

Specific beginning and end dates for open enrollment vary by insurer and type of insurance. If you have health insurance through your employer, the company sets its open enrollment period, which will likely be every fall. The human resources department of your organization will let you know — early and often — when open enrollment approaches, and you’ll get several reminders before it ends.

For the remaining types of insurance that participate in open enrollment, here’s a high-level overview of dates. Please note that some states have different open enrollment dates for plans purchased on the ACA marketplace, but open enrollment most commonly begins and ends on the dates below.

States with different ACA enrollment dates

Since 2010, Americans who don’t have access to employer-sponsored health insurance or aren’t eligible for Medicare/Medicaid coverage can buy insurance through the Affordable Care Act marketplace. While the Affordable Care Act marketplace is a nationwide program, enrollment periods for individual plans vary by state.

To start, investigate ACA marketplace options in your state. Plans on the marketplace are displayed in four categories of increasing cost: Bronze, Silver, Gold, and Platinum. The Bronze category is the cheapest, with the least insurance coverage. Platinum plans are the most expensive but provide coverage of up to 90% of expenses.

If you’d like coverage to begin on Jan. 1, you must enroll by Dec. 15 no matter where you live, although the majority of states extend open enrollment thru Jan. 15, with a few exceptions.

Here are the states with different open enrollment periods:

What should you do during open enrollment?

Even if you’re not anticipating changes to your healthcare plan, open enrollment is the perfect time for insurance housekeeping. The amount you pay for health insurance may vary from year to year, even if you elect the same coverage, so use open enrollment to your advantage.

• Review your current year’s plan. How much does your plan cost for you? Your family? What is your deductible and max out-of-pocket amount?

• Review your options for next year. Will your insurance premiums increase? If so, why? Is there a better option available?

• Review your spouse’s options for next year. If you have a spouse who’s eligible for an employee-sponsored plan at their workplace, is it more advantageous to use their insurance for the family? Is it a better plan? Cheaper?

If you’re purchasing health insurance on the ACA marketplace, it’s vital to compare plan costs each year to ensure you’re getting the best plan at the best price for your (or your family’s) needs.

After reviewing your options, choose your plan and be sure to complete your enrollment paperwork by the deadline; otherwise, you won’t be able to make changes until the next open enrollment season.

How to Compare Medicare Advantage and Get the Best Plan

What is a qualifying event?

You can typically only make changes to your health insurance plan during open enrollment, but there are exceptions. These are known as qualifying events.

Qualifying events for most plans include:

• Marriage or divorce

• Birth or adoption of a child

• Moving to a different state

• Loss of coverage

• Death of the primary insured

If you buy a plan on the ACA marketplace, or through Medicare or Medicaid, you may have additional qualifying events:

• The non-calendar renewal of a grandfathered plan on the ACA marketplace

• A change in citizenship status

• A change in income that affects any subsidy you may receive or that puts you outside the Medicaid coverage gap

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