If you buy your own health insurance in the United States, fall is an important time to review your coverage.

The 2027 ACA Marketplace Open Enrollment Period is approaching, and the dates are not identical in every state. Most states using the federal Marketplace are expected to follow a November 1, 2026, through January 15, 2027 enrollment window, while some states operate their own exchanges and may use different deadlines.

That means waiting until the last minute could be risky—especially if you want your new coverage to begin January 1, 2027.

Quick Answer: When Does 2027 Open Enrollment Start?

For most states, Marketplace Open Enrollment for 2027 health insurance begins:

November 1, 2026

In most federal-platform states, the enrollment period currently runs through:

January 15, 2027

However, the deadline that matters if you want coverage to begin on January 1, 2027 is generally December 15, 2026. People who enroll after December 15 may have coverage that begins February 1, depending on the Marketplace rules that apply to them.

Because state-based marketplaces can set their own schedules, consumers should always check their state’s official Marketplace before relying on a national deadline.

2027 ACA Open Enrollment at a Glance

Important date	What it means
November 1, 2026	Open Enrollment begins in most states
December 15, 2026	Important deadline for January 1 coverage in most states
January 1, 2027	Coverage can begin for eligible people who enroll by the applicable December deadline
January 15, 2027	Final Open Enrollment deadline in most federal-platform states
February 1, 2027	Coverage may begin for qualifying enrollments made after December 15

The exact rules can differ by state and Marketplace.

Why December 15 Is an Important Date

Many people see January 15 as the Open Enrollment deadline and assume they can wait until then and still have insurance starting January 1.

That’s not necessarily the case.

For many Marketplace plans, December 15 is the key date for January 1 coverage. Enrolling later can mean your coverage starts February 1 instead.

So, if you want to avoid an unnecessary gap in coverage, don’t make January 15 your personal target. Giving yourself extra time also allows you to compare premiums, deductibles, provider networks and prescription coverage.

Open Enrollment Dates for Federal Marketplace States

The federal Marketplace serves residents of the following states for 2027:

State	2027 Open Enrollment
Alabama	Nov. 1, 2026 – Jan. 15, 2027
Alaska	Nov. 1, 2026 – Jan. 15, 2027
Arizona	Nov. 1, 2026 – Jan. 15, 2027
Delaware	Nov. 1, 2026 – Jan. 15, 2027
Florida	Nov. 1, 2026 – Jan. 15, 2027
Hawaii	Nov. 1, 2026 – Jan. 15, 2027
Indiana	Nov. 1, 2026 – Jan. 15, 2027
Iowa	Nov. 1, 2026 – Jan. 15, 2027
Kansas	Nov. 1, 2026 – Jan. 15, 2027
Louisiana	Nov. 1, 2026 – Jan. 15, 2027
Michigan	Nov. 1, 2026 – Jan. 15, 2027
Mississippi	Nov. 1, 2026 – Jan. 15, 2027
Missouri	Nov. 1, 2026 – Jan. 15, 2027
Montana	Nov. 1, 2026 – Jan. 15, 2027
Nebraska	Nov. 1, 2026 – Jan. 15, 2027
New Hampshire	Nov. 1, 2026 – Jan. 15, 2027
North Carolina	Nov. 1, 2026 – Jan. 15, 2027
North Dakota	Nov. 1, 2026 – Jan. 15, 2027
Ohio	Nov. 1, 2026 – Jan. 15, 2027
South Carolina	Nov. 1, 2026 – Jan. 15, 2027
South Dakota	Nov. 1, 2026 – Jan. 15, 2027
Tennessee	Nov. 1, 2026 – Jan. 15, 2027
Texas	Nov. 1, 2026 – Jan. 15, 2027
Utah	Nov. 1, 2026 – Jan. 15, 2027
West Virginia	Nov. 1, 2026 – Jan. 15, 2027
Wisconsin	Nov. 1, 2026 – Jan. 15, 2027
Wyoming	Nov. 1, 2026 – Jan. 15, 2027

CMS currently identifies these 27 states as using the federally facilitated Marketplace for plan year 2027.

Important: Arkansas and Oklahoma are classified separately as State-Based Marketplaces operating on the federal platform, so their enrollment arrangements should not simply be assumed from the 27-state list.

States With Their Own Health Insurance Marketplaces

Some states operate their own Marketplace websites rather than relying entirely on HealthCare.gov.

For 2027, these include:

California
Colorado
Connecticut
District of Columbia
Georgia
Idaho
Illinois
Kentucky
Maine
Maryland
Massachusetts
Minnesota
Nevada
New Jersey
New Mexico
New York
Oregon
Pennsylvania
Rhode Island
Vermont
Virginia
Washington

State-based exchanges have more flexibility over their enrollment schedules, which is why you should not assume that every state follows exactly the same deadline.

For example, some states have historically extended their enrollment periods beyond the federal deadline, while others use shorter windows.

What If You Miss Open Enrollment?

Missing Open Enrollment does not automatically mean you have to remain uninsured for the rest of the year.

You may qualify for a Special Enrollment Period (SEP) if you experience certain qualifying life events.

Common examples include:

Losing Health Insurance

If you lose qualifying health coverage—for example, because you leave a job and lose employer-sponsored insurance—you may be able to enroll outside the normal Open Enrollment period.

Getting Married

Marriage can create an opportunity to enroll in or change Marketplace coverage.

Having a Baby

The birth or adoption of a child can create a Special Enrollment Period.

Moving

A move that qualifies under Marketplace rules may allow you to enroll or change plans.

Other qualifying circumstances may also apply. HealthCare.gov advises people who experience a qualifying life event to check their eligibility rather than waiting for the next annual enrollment period.

How Long Do You Have to Enroll After a Qualifying Event?

The timing depends on the event and the applicable Marketplace rules.

In many common situations, consumers have a 60-day window around a qualifying life event to select coverage.

Because the exact rules can depend on the circumstances, it’s better to check your eligibility immediately after losing coverage, moving, getting married or experiencing another qualifying event.

What If You Don’t Qualify for a Special Enrollment Period?

You may still have other options, depending on your circumstances and state.

For example, you could potentially qualify for:

Medicaid
CHIP
Employer-sponsored coverage
Another qualifying source of health insurance
Certain individual-market alternatives available in your state

Medicaid and CHIP are particularly important because applications are generally not restricted to the annual Marketplace Open Enrollment period. HealthCare.gov says eligible people can apply for these programs outside Open Enrollment.

Short-term health insurance may also be available in some states, but it is not the same as comprehensive ACA Marketplace coverage. Benefits, eligibility, renewability and coverage for pre-existing conditions can differ substantially.

Should You Automatically Renew Your Current Health Plan?

Not necessarily.

One of the biggest mistakes people make during Open Enrollment is simply letting their existing plan renew without comparing alternatives.

Your situation may have changed since the previous year.

For example:

Your income may be different.
Your household size may have changed.
Your doctor may no longer be in the plan’s network.
Your prescriptions may have changed.
Your deductible may be higher.
Another plan may offer better coverage for your expected medical needs.

HealthCare.gov recommends updating your expected income and household information and comparing available plans before renewing or selecting coverage.

What Should You Compare Before Choosing a Plan?

Don’t look only at the monthly premium.

A cheaper premium can sometimes come with higher out-of-pocket costs.

Before selecting a plan, compare:

1. Monthly Premium

This is the amount you pay each month to keep your health insurance active.

2. Deductible

The deductible is the amount you generally pay for covered services before the plan begins paying according to its benefits.

3. Out-of-Pocket Maximum

This is an important number because it can affect your financial exposure when you need significant medical care.

4. Doctor and Hospital Network

Check whether your preferred doctors, specialists and hospitals participate in the plan.

5. Prescription Coverage

If you regularly take medication, check whether your prescriptions are covered and what your expected costs will be.

HealthCare.gov recommends considering total health care costs—not just the premium—when comparing Marketplace plans.

Can You Check Health Insurance Prices Before Open Enrollment?

You can often preview Marketplace plan information and estimated prices using the Marketplace tools.

Your estimated premium can depend on factors such as your ZIP code, household size and expected income. The actual price and savings are determined through the application process.

Preparing before November can therefore make the enrollment process much easier.

A Simple Open Enrollment Checklist

Before choosing your 2027 health insurance plan, gather:

✓ Expected 2027 household income

✓ Household information

✓ Current insurance details

✓ Preferred doctors

✓ Preferred hospitals

✓ Prescription list

✓ Recent medical needs

✓ Budget for monthly premiums

✓ Budget for deductibles and out-of-pocket costs

Having this information ready can make comparing plans considerably easier.

When Should You Start Looking for 2027 Coverage?

You don’t have to wait until the final week of Open Enrollment.

A better approach is to start preparing before November 1.

September–October 2026

Review your current insurance and estimate your upcoming income and health-care needs.

November 2026

Start comparing available 2027 plans when enrollment opens.

December 2026

Try to complete your enrollment by the applicable deadline if you want coverage beginning January 1.

January 2027

If you haven’t enrolled yet, check your state’s final deadline immediately. Waiting until the final day can leave little room to correct application problems.

The Bottom Line

For many Americans, 2027 Marketplace Open Enrollment begins November 1, 2026. The commonly cited final date in most federal-platform states is January 15, 2027, but December 15, 2026 is the critical date for January 1 coverage in many circumstances. State-run exchanges may use different enrollment schedules.

Don’t choose a plan based only on its monthly premium. Compare the deductible, out-of-pocket maximum, provider network, prescription coverage and your expected health-care needs.

And if you miss Open Enrollment, don’t assume you’re out of options. A qualifying life event could make you eligible for a Special Enrollment Period, while Medicaid or CHIP may be available to people who meet their eligibility requirements.

For the most accurate deadline, always verify the enrollment dates for your state before submitting an application.

When Is Open Enrollment for 2026–2027? 2027 Health Insurance Dates by State