The first day of open enrollment for health insurance under the Affordable Care Act began Wednesday.

  • Open enrollment for health insurance begins Nov. 1
  • People without health coverage are subject to a penalty come tax time
  • Those under ACA health care plans will receive notice if ACA ends  

Here's what you need to know before you apply for coverage:

1. Important Dates

  • Enrollment begins: Nov. 1
  • Enrollment ends: Dec. 15

The Trump administration has cut the enrollment period down to run six weeks shorter. It has also slashed advertising by 90 percent and reduced budgets for groups that help people choose a plan.

2. Costs

If you don't have health coverage and decide to forgo signing up for 2018 coverage, you'll owe a penalty at tax time with some exceptions.

A dozen states have their own health-insurance exchanges and are free to make their own decisions on spending and the enrollment period. But for Florida and the rest of the U.S., which relies on the federal marketplace, enrollment will be more difficult — and costly.

In addition to cutting the enrollment period, the federal marketplace's website,, will be shut down for 12 hours almost every Sunday during open enrollment.

Many states may also see double-digit health-insurance rate increases; in Florida, the rate hike is expected to be about 45 percent. Premiums for the most popular plans are up about 34 percent on average.

That said, consumers can still be eligible for the federal subsidy.

3. What do I need to enroll?

The marketplace recommends you have the following information handy when you enroll:

  • How many people in your household you would like to enroll.
  • The home/mailing address of everyone wanting to apply for coverage.
  • Birth dates of everyone who wants to enroll.
  • Social Security numbers of those wanting to enroll.
  • If you're relying on a professional to help you apply, have their information.
  • Documentation information for legal immigrants.
  • How you usually file your taxes. 
  • Employer and income information for everyone in your household (it would be easiest to have pay stubs available or W-2 forms).
  • Your estimated household income for 2018.
  • Policy numbers for current health plans currently covering members of your household.
  • A completed Employer Coverage Tool for every job-based plan you or someone in your household is eligible for. 
  • IDs from any current health care plans you currently have.

4. What if the Affordable Care Act or "Obamacare" is repealed?

Proposals to repeal the ACA have included wind-down periods, so those with ACA health-care plans would receive notice if the program ends.

5. Where do I sign up to enroll?

You can sign up during open enrollment at HealthCare.Gov.

Contact the 24-hour assistance line at 1-800-318-2596 if you need assistance or have questions about enrollment.

Information from the Associated Press was used in this report.