ACA Open Enrollment 2027: The December 15 and January 15 Deadlines
Figures checked November 11, 2026 against primary sources
Open enrollment for 2027 health plans on HealthCare.gov runs from November 1, 2026 to January 15, 2027. The date most people need is Tuesday, December 15, 2026: pick a plan by then and your coverage can start January 1. Enroll between December 16 and January 15 and it starts February 1. After January 15 you can sign up only if you qualify for a Special Enrollment Period.
2027 Open Enrollment Dates
| Date | What happens |
|---|---|
| Sunday, November 1, 2026 | Open enrollment starts. First day to enroll in, renew or change a Marketplace plan for 2027. |
| Tuesday, December 15, 2026 | Last day to enroll in or change plans for coverage that starts January 1. |
| Friday, January 1, 2027 | Coverage starts for people who enrolled by December 15 and paid their first premium. |
| Friday, January 15, 2027 | Open enrollment ends. Last day to enroll in or change a Marketplace plan for 2027. |
| Monday, February 1, 2027 | Coverage starts for people who enrolled December 16 through January 15 and paid their first premium. |
| January 16 to October 31, 2027 | You can get coverage only if you qualify for a Special Enrollment Period. |
Medicaid and the Children's Health Insurance Program (CHIP) are different: you can apply for them at any time of year.
Why December 15 Matters
January 15 is the last day to sign up, but it is not the deadline for a January 1 start. Miss December 15 and you have no Marketplace coverage in January, even if you enroll in early January.
- Coverage starts only after you pay. HealthCare.gov ties both start dates to paying your first premium. Choosing a plan is not enough.
- Already enrolled? November 1 is also the first day to renew or change your plan. Changes made by December 15 apply from January 1; changes made December 16 to January 15 apply from February 1.
- Check your 2027 price before you renew. Our ACA subsidy cliff guide covers what changed for 2027 premium tax credits, the income lines and how the credit is worked out.
After January 15: Special Enrollment
From January 16, you can enroll in or change a Marketplace plan only if a life change gives you a Special Enrollment Period. HealthCare.gov lists these, among others:
- Lost health coverage in the past 60 days, or you expect to lose it in the next 60 days.
- Lost Medicaid or CHIP in the past 90 days.
- COBRA ended. You have 60 days to enroll after COBRA expires or is no longer available. Dropping COBRA early by choice does not count.
- Got married in the past 60 days. Pick a plan by the last day of the month and coverage can start the first day of the next month.
- Had a baby, adopted a child or placed a child for foster care. Coverage can start the day of the event, even if you enroll up to 60 days later.
Rules and paperwork differ by life change. Check the HealthCare.gov Special Enrollment Period page for your situation.
State-Run Exchanges
The November 1 to January 15 window is the default. Federal rules let a state that runs its own exchange keep open enrollment going past January 15. A state exchange whose 2024 open enrollment started before November 1, 2023 and ended before January 15, 2024 may also keep starting before November 1, as long as its window runs at least 11 weeks without a break.
So if your state has its own exchange, its last day can differ from HealthCare.gov. We have not listed state dates here because we have not checked each state's site; use your state exchange's own calendar.
Did the Court Cases Change the Dates?
No, not for this enrollment period, according to CMS. The federal regulations as printed online still contain a provision that, for coverage starting in 2027, would end open enrollment by December 31 and cap it at 9 weeks. On June 12, 2026, the U.S. District Court for the District of Maryland struck certain provisions of the 2025 Marketplace Integrity and Affordability rule (City of Columbus v. Kennedy). In a July 27, 2026 statement, CMS said HHS has not altered the open enrollment dates and that open enrollment on the federal Marketplace begins November 1, 2026 and ends January 15, 2027.
On July 16, 2026, in a second City of Columbus v. Kennedy case, the same court stayed several parts of the separate 2027 payment rule while that case is pending. CMS's August 4, 2026 statement repeats the November 1 to January 15 dates. The litigation is ongoing, so check HealthCare.gov for any change.
Medicare and Federal Employee Plans Are Separate
- Medicare. Medicare's open enrollment runs October 15 to December 7, and changes start January 1. It covers Medicare Advantage and drug plans, not Marketplace plans. See our Medicare open enrollment guide.
- Federal employees and retirees (FEHB). OPM's Open Season runs November 9 to December 14, 2026. See FEHB premiums 2027.
Before You Enroll
- Log in and review, even if you plan to keep your plan. You can compare 2027 plans on HealthCare.gov now.
- Estimate your 2027 income. The premium tax credit depends on it. Our subsidy cliff guide explains the income lines.
- Compare total costs, not only the premium. Deductibles and out-of-pocket limits differ by plan. See how to choose a health insurance plan.
- Pay the first premium. Coverage does not start until you do.
- Questions? The Marketplace call center is 1-800-318-2596.
Sources & Methodology
- HealthCare.gov: When can you get health insurance? (dates and deadlines) and Special Enrollment Periods.
- CMS: statement of July 27, 2026 and statement of August 4, 2026 on City of Columbus v. Kennedy and the open enrollment dates.
- 45 CFR 155.410(e)(4): the November 1 to January 15 period and the State Exchange options.
- Medicare.gov: Joining a plan. OPM: Open Season.
Method notes. All dates were re-read from the pages above on November 11, 2026 (the OPM Open Season page on November 9, 2026). Days of the week are from the calendar. State exchange deadlines are not listed because we did not read each state's site.
This article is educational and is not insurance, tax or legal advice. Wealthy Pot is not affiliated with HealthCare.gov, CMS or any insurer. Dates were checked against HealthCare.gov, CMS and federal regulations on 2026-11-11 and can change if a court or HHS acts. Confirm your deadline on HealthCare.gov or your state exchange.
FAQ
What is the deadline for Obamacare for 2027?
On HealthCare.gov, open enrollment ends January 15, 2027. To have coverage from January 1, 2027, enroll by December 15, 2026 and pay your first premium.
What happens if I enroll on January 10?
If you pick a plan between December 16 and January 15 and pay the first premium, coverage starts February 1, 2027.
Can I get health insurance after January 15?
Only with a Special Enrollment Period, for example after losing other coverage, getting married or having a baby. Medicaid and CHIP accept applications at any time.
Is the deadline different in my state?
It can be. States that run their own exchange may end open enrollment after January 15. The HealthCare.gov dates apply in states that use HealthCare.gov.
Did the shorter open enrollment rule take effect?
Not for this period. After a June 12, 2026 court order, CMS said HHS has not altered the dates: November 1, 2026 to January 15, 2027 on the federal Marketplace.
Do I need to do anything if I already have a Marketplace plan?
You can renew or change your plan from November 1. Review it by December 15 if you want any change to start January 1.
Cite This Page
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"ACA Open Enrollment 2027: The December 15 and January 15 Deadlines." Wealthy Pot, 2026. https://wealthypot.com/aca-open-enrollment-2027/
