Deadlines and special enrollment periods
Open enrollment on HealthCare.gov runs from November 1 through January 15 in most states. Per the official dates and deadlines page, enroll by December 15 for coverage starting January 1, and between December 16 and January 15 for coverage starting February 1. For 2027 coverage, that means November 1, 2026 through January 15, 2027 in most of the country.
State-run exchanges set their own calendars. Per healthinsurance.org's exchange calendar, Idaho starts earliest, October 15 to December 15; Rhode Island ends December 31; Virginia ends January 29; Massachusetts runs to January 23; and the District of Columbia, Illinois, New York and Pennsylvania run to January 31. Check your own state before assuming January 15.
Miss open enrollment without a qualifying event and you generally wait a year. Medicaid and CHIP have no enrollment window and accept applications any month, so check eligibility first if your income dropped. Short-term plans are not a substitute, and losing one does not open a marketplace enrollment window.
Outside open enrollment you need a special enrollment period. HealthCare.gov lists the qualifying categories, and you generally have 60 days from the event to enroll, extended to 90 days for a loss of Medicaid or CHIP coverage:
- Loss of qualifying health coverage. Job loss, aging off a parent's plan at 26, expiration of COBRA, divorce ending eligibility, or losing Medicaid or CHIP. Voluntarily dropping coverage does not count.
- Household change. Marriage, divorce or legal separation, birth, adoption, foster placement, or a death in the household that changes eligibility.
- Change of residence. A permanent move to a new ZIP code or county with different plan options, moving to or from school or seasonal work, or moving to the US from abroad. You generally must have had coverage for one of the prior 60 days.
- Change in eligibility for help paying costs. An income change that newly qualifies you for or removes you from premium tax credits or cost-sharing reductions.
- Other qualifying situations. Gaining citizenship or lawful presence, release from incarceration, starting or ending AmeriCorps service, or a marketplace or plan error that affected your enrollment.
You will usually be asked to document the event, so keep the termination letter, lease, marriage certificate or birth record. Enrolling in the first 15 days after some events can start coverage the first of the next month; later enrollments often start the month after that.
Networks, essential benefits and why silver plans are priced strangely
Three plan types dominate the individual market. An HMO requires you to use in-network providers except in emergencies and often requires a primary care referral for specialists. An EPO also pays nothing out of network but usually does not require referrals. A PPO covers out-of-network care at a higher cost share and is the most flexible and most expensive. A small number of markets offer POS plans, which blend referral requirements with limited out-of-network coverage.
| Plan type | Out-of-network coverage | Referral required | Typical relative premium |
|---|---|---|---|
| HMO | Emergencies only | Usually yes | Lowest |
| EPO | Emergencies only | Usually no | Low to moderate |
| POS | Reduced coverage | Usually yes | Moderate |
| PPO | Yes, at higher cost share | No | Highest |
Silver loading, and why gold sometimes costs less than silver
This is the strangest feature of the marketplace and it is worth understanding. Insurers are legally required to provide cost-sharing reductions to eligible silver enrollees. The federal government stopped reimbursing insurers for those reductions in October 2017. As KFF explains, insurers responded by loading the cost of CSRs onto silver premiums specifically, a practice regulators permitted. KFF found silver premiums rose roughly 17 percentage points more than bronze premiums as a result.
Two consequences follow. First, because premium tax credits are pegged to the benchmark silver plan, inflated silver premiums produce larger subsidies that can be spent on any tier, which makes bronze and gold plans unusually cheap for subsidized buyers. Second, in many rating areas a gold plan genuinely costs less than a silver plan with better coverage. If you do not qualify for cost-sharing reductions, always price gold against silver before deciding.
What every plan must cover
All qualified health plans cover the ten essential health benefits, cannot impose annual or lifetime dollar limits on them, cannot exclude pre-existing conditions, and must cover a list of preventive services with no cost sharing when delivered in network. Adult dental and vision are excluded from the essential benefits, which is why standalone dental and vision plans exist and are sold alongside marketplace coverage.
Plan availability, standardized designs, network breadth and state-specific benefit mandates all vary by state and rating area. Confirm details for your county before you enroll, and see our guides on how subsidies are calculated and what health insurance costs.
Sources & further reading
- HealthCare.gov — Health plan categories and actuarial values
- HealthCare.gov — What marketplace plans cover, the ten essential health benefits
- HealthCare.gov — Dates and deadlines for health insurance
- HealthCare.gov — Special enrollment periods and qualifying events
- KFF — What we know so far about 2026 marketplace enrollment, premiums and deductibles
- KFF — Explaining cost-sharing reductions and silver loading
- healthinsurance.org — Open enrollment dates by state exchange