What are the deadlines for the ACA’s open enrollment period?

Note: The federal government has proposed a new open enrollment schedule, running from November 1 through December 15, starting in the fall of 2025. If finalized as proposed, this window will apply nationwide, including in states that run their own exchanges/Marketplaces. This page will be updated with more details if and when that proposal is finalized.

In most states – including Minnesota,⁴ Maine,⁵ and the District of Columbia,⁶ and the 31 states that use HealthCare.gov – December 18, 2024 was the deadline to get a plan that took effect January 1, 2025.⁷ Enrollments completed on or after December 19 took effect February 1 instead. (Note that this is an extension; the normal deadline in most states is December 15.) But there were some later deadlines for a January 1 effective date:

• In California,⁸ Maryland,⁹ Nevada,¹⁰ New Jersey,¹¹ New Mexico,¹² Rhode Island,¹³ and Virginia,¹⁴ coverage took effect on January 1 as long as the application was completed by December 31.
• In Idaho,¹⁵ the deadline for a January 1 effective date was publicized as December 16. But there were questions about why Idaho's enrollment window was not extended to comply with rules that CMS finalized in 2024. We followed up with Your Health Idaho (the state-run Marketplace) and they clarified by email that anyone who missed the December 16 deadline "can contact our support center to enroll." The phone number for the Your Health Idaho call center is 855-944-3246. To comply with the federal rules that require open enrollment to last at least 11 weeks, Your Health Idaho had to keep this option open until December 31.
• In Massachusetts, the deadline for a January 1 effective date was December 23.¹⁶
• In Georgia, the deadline for a January 1 effective date was December 20.¹⁷

The rest of the state-run exchanges – Colorado, Connecticut, Kentucky, New York, Pennsylvania, Vermont, and Washington – switched to enrolling people in coverage with a February 1 effective date starting on December 16 (Colorado and Kentucky had last-minute extensions to their normal December 15 deadline for a January 1 effective date, if applicants called the exchange for assistance; those extensions ended within a few days).

These deadlines can change from one year to the next, so never assume that your state will allow a January 1 effective date if you enroll after December 15; always double-check, even if that option was available in previous years.

Open enrollment used to end on December 15 in most states, but the Biden-Harris administration added a one-month extension that took effect for the 2022 plan year and will continue to be used from now on. This applies to the 31 states that use HealthCare.gov for 2025. The other 19 states and DC are free to follow that same schedule – most do – or set their own schedule.

*As noted above, there were questions about why Idaho's enrollment window has not been extended to comply with rules that CMS finalized in 2024, and Your Health Idaho said that they would still enroll people who called their call center (855-944-3246) after December 16. To comply with the federal rules that require open enrollment to last for at least 11 weeks, Your Health Idaho had to accept applications for 2025 coverage through December 31, 2024.

Outside of ACA's open enrollment window, enrollment is only available with a special enrollment period

After open enrollment ends, people can normally only purchase coverage if they have a special enrollment period (SEP). Most SEPs are triggered by a specific qualifying event such as:

• Marriage (since 2017, this generally only applies if at least one spouse already had coverage before the wedding, although there are some exceptions),
• Becoming a U.S. citizen,
• Birth or adoption,
• Involuntary loss of other health coverage.
• A permanent move to an area where new health plans are available (since July 2016, this only applies in most cases if you already had coverage prior to your move).
• Here’s a complete guide to qualifying events in the individual market, and their associated special enrollment periods. Note that in most cases, special enrollment periods can be used to obtain replacement coverage, but not to go from being uninsured to insured. But some qualifying life events, such as the birth of a baby, will allow a household to obtain new coverage even if they weren't previously insured.

Regardless of whether you purchase insurance through the exchange or off-exchange, the annual open enrollment window applies, and special enrollment periods are necessary to enroll at any other time of the year.

Open enrollment schedule has varied over time

Although open enrollment is now set at November 1 - January 15 in most states, it has varied quite a bit over the years. And the federal government has proposed yet another change, starting with the enrollment window in the fall of 2025 (if finalized as proposed, these new dates will apply nationwide, including in states that run their own marketplaces). In the federally-run marketplaces, the following enrollment windows have been used (with some last-minute extensions, and with somewhat different schedules used by the state-run marketplaces):

• 2014 coverage: October 1, 2013 through March 31, 2014
• 2015 coverage: November 15, 2014 through February 15, 2015
• 2016 coverage: November 1, 2015 through January 31, 2016
• 2017 coverage: November 1, 2016 through January 31, 2017
• 2018 coverage: November 1, 2017 through December 15, 2017
• 2019 coverage: November 1, 2018 through December 15, 2018
• 2020 coverage: November 1, 2019 through December 15, 2019
• 2021 coverage: November 1, 2020 through December 15, 2020
• 2022 coverage: November 1, 2021 through January 15, 2022
• 2023 coverage: November 1, 2022 through January 15, 2023
• 2024 coverage: November 1, 2023 through January 16, 2024 (one-day extension due to a federal holiday)
• 2025 coverage: November 1, 2024 through January 15, 2025
• 2026 coverage: (Proposed) November 1, 2025 through December 15, 2025

Louise Norris is an individual health insurance broker who has been writing about health insurance and health reform since 2006. She has written dozens of opinions and educational pieces about the Affordable Care Act for healthinsurance.org. Her state health insurance marketplace updates are regularly cited by media who cover health reform and by other health insurance experts.