Marketplace open enrollment 2027: dates and deadlines

Once a year, the Health Insurance Marketplace opens for anyone to enroll, switch or renew a plan without needing a reason. Outside that window, a reason is required. Knowing the dates, and knowing which life events reopen the door, is most of what this decision comes down to.

The dates that matter

November 1, 2026 is the first day you can enroll in, renew or change a plan for 2027 coverage. Nothing before that date counts unless you qualify for a special enrollment period, covered below.

December 15, 2026 is the date to actually aim for. Enroll or change your plan by then and coverage starts January 1, 2027 with no gap between your old coverage and the new plan.

January 15, 2027 is the close of open enrollment. Enroll between December 16 and January 15 and coverage starts February 1, which means a full month without coverage under the new plan if your old coverage ended December 31.

Miss January 15 entirely and the door closes until the following November, unless something happens in your life that reopens it.

What reopens the window

A special enrollment period lets you enroll outside the annual window when a listed life event happens. Marriage, a new baby or an adopted or fostered child, divorce that costs you coverage, moving to a new ZIP code or county, and losing other health coverage all qualify. Each has its own 60-day clock and its own start date for the new coverage, so the details differ by event rather than following one rule.

Losing job-based coverage, including COBRA, is the one most people run into. If your employer's plan ends, if a family member's employer plan drops you, or if your COBRA coverage runs out or becomes unavailable, you get 60 days from the day coverage ends to enroll in a Marketplace plan.

That 60-day window is not the same as open enrollment, and it does not wait for November. A layoff in March opens a 60-day Marketplace window in March, whatever the calendar otherwise says.

The COBRA trap, from the other side

The COBRA explainer covers this from the COBRA side; the rule is the same rule, worth restating here because it decides which direction people move in.

Voluntarily cancelling COBRA, or simply stopping payment, does not open a special enrollment period. HealthCare.gov states it plainly: the Marketplace window applies when COBRA expires or becomes unavailable, not when you choose to end it early. Someone who assumes they can switch to a cheaper Marketplace plan whenever they want and drops COBRA to do it can find themselves with no coverage until the next November.

What does open the window: COBRA running to the end of its term, an employer ending its contribution so you would face the full 102 percent cost, or you are still within 60 days of the original job loss. During open enrollment itself, November 1 to January 15, none of this matters, because anyone can switch for any reason at all.

How much you would pay

The Marketplace calculates savings on the income you estimate for the year you want coverage, 2027, not the return you already filed. That distinction catches people who assume a subsidy from a prior year still applies; it does not, and an outdated estimate can mean paying back a subsidy at tax time or missing one you were owed.

Household counts everyone you will claim as a tax dependent, including anyone who does not need the coverage themselves. The Marketplace's own application is where an exact number appears, because it depends on where you live, your household size and the plans available in your area, none of which a general explainer can state accurately for every reader.

What Medicare open enrollment has to do with this

If you are turning 65 rather than losing a job, the relevant deadline is not this one. Medicare open enrollment runs October 15 to December 7 and covers a different decision, choosing or switching a Medicare Advantage or Part D plan. The two windows exist side by side and are frequently confused because both fall in the same stretch of the calendar; Marketplace coverage and Medicare are not interchangeable, and someone eligible for Medicare generally cannot also buy subsidized Marketplace coverage.

What to do before November 1

Nothing is required before the window opens, but three things save time once it does: know your household size and estimated 2027 income, know whether your current coverage, if any, is ending on its own or by your choice, and know the deadline that applies to your situation. For most people that deadline is December 15, and missing it by even a day pushes the start date to February 1. Who to contact at Medicare is the reference if the question turns out to be about Medicare rather than the Marketplace after all.