For 2027 coverage, open enrollment runs November 1, 2026 through January 15, 2027 in most states. But January 15 is not the date that matters most. In most states, coverage starting January 1 means enrolling by December 15, 2026. Enroll after that and your plan generally will not start until February 1 — leaving you uninsured for a month you probably assumed you were covered. Maryland is the exception among the states we serve, and gives you until December 31.
The two dates people mix up
Nearly every deadline reminder you will see this season names a single date. That is where the confusion starts, because open enrollment has two, and they do different jobs.
December 15 is the coverage date in most states. Choose a plan on or before it, pay your first premium by the carrier’s binding deadline, and you are covered from January 1. January 15 is the door-closing date. You can still enroll between December 16 and January 15, but that coverage almost always starts February 1 instead. Maryland runs its own calendar and holds the coverage date open until December 31 — worth knowing if you moved there from a HealthCare.gov state.
Both errors are common and both are expensive. Some people see “December 15” described as the deadline, miss it, and assume they are locked out for the year — when they actually had another month to enroll. Others enroll on January 10 expecting to be covered immediately, then discover in late January that their plan does not begin for another week. If you have a procedure scheduled, a prescription to refill, or a chronic condition to manage, that gap is not a technicality.
Deadlines for the states we serve
Castro Coverage is actively licensed in 24 states. Seven of them run their own marketplaces rather than using HealthCare.gov, which means separate portals, separate rules, and in one case a separate deadline.
| States | Marketplace | Enroll by, for Jan 1 | Final deadline |
|---|---|---|---|
| Alabama, Arkansas, Florida, Indiana, Iowa, Kansas, Michigan, Missouri, Nebraska, North Carolina, Ohio, Oklahoma, South Carolina, South Dakota, Tennessee, Texas, Utah | HealthCare.gov | Dec 15, 2026 | Jan 15, 2027 |
| Maryland | Maryland Health Connection | Dec 31, 2026 | Jan 15, 2027 |
| Colorado, Georgia, Illinois, Kentucky, Nevada | State-based exchange | Dec 15, 2026 (confirm) | Jan 15, 2027 |
| Virginia | Virginia’s Insurance Marketplace | Dec 15, 2026 (confirm) | Jan 29, 2027 |
Deadlines confirmed as of September 1, 2026. State-based exchanges set their own calendars and can adjust them; always confirm against your state’s marketplace before relying on a date.
Why this year’s deadline is not settled
There is an unusual complication for 2027. A federal rule finalized in 2025 would have permanently shortened open enrollment for HealthCare.gov states, ending it on December 15 with no January window at all. In June 2026 a federal court vacated that rule. The Department of Health and Human Services appealed in July, and oral arguments are scheduled for late October 2026 — days before enrollment opens.
For now, HHS has confirmed that HealthCare.gov states will run through January 15, 2027, and that is the schedule reflected above. But the appeal is live, and an outcome during the enrollment season could change the final deadline while people are still shopping.
Do not plan around January 15. Treat December 15 as your deadline, because it is the only date in this picture that is both stable and tied to coverage actually starting on January 1. If the January window survives the appeal, you have gained a safety net rather than lost anything.
If you miss open enrollment
Outside these windows you generally cannot buy a marketplace plan until the following year — unless you qualify for a Special Enrollment Period. Qualifying life events include:
- Losing job-based coverage, including at the end of COBRA
- Moving to a new state, or a move within your state that changes the plans available to you
- Marriage, divorce, birth or adoption of a child
- A change in income that changes your subsidy eligibility
- Turning 26 and aging off a parent’s plan
Most Special Enrollment Periods give you 60 days from the qualifying event. Miss that window too and you are usually waiting for the next open enrollment, so it is worth a call the week something changes rather than the month after.
Getting it right the first time
Deadlines are the easy part of this to write down and the hard part to act on, because the plan you pick under time pressure in December is the plan you live with all year. If you want a second set of eyes before December 15 — on which deadline applies to you, on whether your doctors are still in network, or on what the loss of enhanced subsidies did to your actual cost — that is what we do, at no charge to you.
General information as of September 2026, not a quote, an offer of coverage, or a guarantee of eligibility. Marketplace rules, deadlines and subsidy eligibility change year to year and by state.
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