A year ago, many people expected the Patient Protection and Affordable Care Act, better known as Obamacare, to be history by now. Yet at least for now, Obamacare lives on, and open enrollment began as anticipated during the fall. The official open enrollment period for Obamacare ran from Nov. 1 to Dec. 15, and even those in several areas that got extensions due to hurricane impacts saw them end on Dec. 31, leaving them without an option to sign up for 2018 coverage under the ACA right now.

But as of Jan. 8, residents in six states and the District of Columbia are still covered by open enrollment periods. That's because state healthcare exchanges had the option to set their own deadlines for coverage under the Affordable Care Act, and several jurisdictions took advantage of that ability to broaden the length of time that residents would be eligible to sign up. Below, we'll look at the places featuring deadlines for ACA open enrollment in January.

Health insurance benefits form with stethoscope, calculator, and pen on top.

Image source: Getty Images.

1. Colorado: Jan. 12

Residents of Colorado have just a few days left to sign up for Obamacare open enrollment for 2018. The state's Connectforhealthco.com website gives access to the state's health insurance exchange. Colorado had 162,000 people sign up for Obamacare for the 2017 coverage year, according to figures from the Kaiser Family Foundation.

Those who sign up at this point won't have coverage retroactive to the beginning of the year. However, policies obtained now will be effective starting Feb. 1.

2. Minnesota: Jan. 14

Minnesota's MNsure program has an open enrollment deadline of Jan. 14. Those who wanted coverage that began on Jan. 1 had to sign up by Dec. 20, but coverage should take effect by Feb. 1.

Last year, 110,000 Minnesota residents signed up for Obamacare coverage for 2017. Based on early numbers, more than 108,500 people had signed up for the program in time to get Jan. 1 coverage, which was 12.5% greater than the corresponding figure last year.

3. Washington: Jan. 15

The Washington Health Benefit Exchange offers residents the opportunity to sign up for coverage under Obamacare through Jan. 15. Dec. 15 was the last day on which applicants could have coverage begin as of the beginning of 2018, but those who sign up now can expect a February start date for their policies. Washington had about 225,000 residents sign up for coverage under the ACA last year.

4. Massachusetts: Jan. 23

The Massachusetts Health Connector set a Jan. 23 deadline for open enrollment under the Affordable Care Act. Those who sign up and pay for premiums by that deadline will get a Feb. 1 coverage start date.

Early reports showed intense interest in Obamacare during this year's open enrollment period, with more than 40% greater participation during the first few weeks of the period than had signed up at the same time in 2016. Massachusetts counted almost 267,000 residents with ACA coverage for 2017.

5. D.C.: Jan. 31

The D.C. Health Link set a deadline of Jan. 31 to sign up for Obamacare for 2018. Those who sign up by Jan. 15 will be able to start coverage as of Feb. 1, while those who wait until closer to the final deadline will have to wait until March 1 for coverage to take effect.

Relatively few D.C. residents took advantage of Obamacare in 2017. Just 21,000 selected a marketplace plan for that year.

6. New York: Jan. 31

The NY State of Health program also picked Jan. 31 for its deadline, with the state touting the need for longer open enrollment periods. As the agency said in a press release, "A longer enrollment period has been shown to increase enrollment of younger individuals."

Even with the longer deadline, New York hasn't seen a huge amount of interest in the program. Given New York's high population, the roughly 243,000 people who chose exchange-based Obamacare coverage for 2017 according to the Kaiser Family Foundation was a relatively low number.

7. California: Jan. 31

Finally, California residents will be able to sign up for ACA coverage through the end of January. The Covered California program won't be able to offer a Jan. 1 effective date for coverage, but those who enroll by Jan. 19 should be able to get a Feb. 1 start date. Those who file toward the end of the month will have to settle for March 1 coverage.

California ranked second in the number of people using ACA coverage in 2017. More than 1.55 million residents used the program last year.

Don't miss out

People who live in these locations can still sign up for coverage for 2018 under the Affordable Care Act, but time is running out. If you want to take advantage of the benefits that Obamacare can provide, be sure to act quickly before the window closes to sign up for health insurance once and for all.

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