Open Enrollment 2027: ACA Key Dates and 5 Steps

Open enrollment for 2027 health coverage on HealthCare.gov runs November 1, 2026 through January 15, 2027. The date that matters most is December 15: enroll by then and coverage starts January 1, but enroll one day later and coverage starts February 1. This guide gives the key dates and five steps to enroll without missing the window.

Summary

The Centers for Medicare and Medicaid Services (CMS) states that open enrollment for 2027 coverage on HealthCare.gov begins November 1, 2026 and runs through January 15, 2027. HealthCare.gov lists December 15, 2026 as the last day to enroll in or change plans for coverage that starts January 1, 2027. Plans picked from December 16 through January 15 start February 1, 2027, once the first premium is paid. After the window closes, enrollment generally requires a Special Enrollment Period, which depends on a qualifying life event. The five steps below cover checking your state, gathering information, comparing plans, checking doctors and prescriptions, and enrolling before the deadline that fits your start date.

The 2027 Enrollment Calendar

The table shows why December 15 is the date to circle. The window stays open for another month after it, but the start date moves. Enrolling on December 15 gives you coverage on January 1. Enrolling on December 16 gives you coverage on February 1, which leaves January without a Marketplace plan. Coverage starts only after the first premium is paid, so finishing the application is not the same as being covered.

5 Steps to Enroll

Step 1: Check whether your state uses HealthCare.gov

Most states use HealthCare.gov, but some run their own Marketplace with their own dates. A state-run Marketplace can set a different deadline than the federal one. Check your state on HealthCare.gov first, and if your state has its own site, use that site's dates instead. This step takes a minute and keeps you on the right calendar.

Step 2: Gather your household and income information

Before you start the application, collect the information the Marketplace asks for: household size, expected income, and the Social Security numbers and birth dates of everyone applying. Savings are generally based on the income you expect for the coverage year, so estimate the coming year rather than copying last year's tax return. If your estimate changes later, the savings amount can change too, so take time to get it right. Current enrollees should also update their details, because the same plan can cost a different amount next year.

Step 3: Compare plans by total cost, not premium alone

CMS states that on average Americans have access to 100 different plans and five to six different insurance companies in 2027, so the choice is wide. Compare the monthly premium together with the deductible and the out-of-pocket maximum, because a low premium with a high deductible can cost more over the year than a higher premium with lower cost sharing.

CMS also states that more than 75% of people who buy coverage through HealthCare.gov will continue to have access to premiums at or below $50 in 2027, and that for people eligible for tax credits, nearly 90% of the lowest-cost premium is paid for by the federal government. Those figures describe the market as a whole. Check the savings you personally qualify for on your own application rather than assuming the average applies to you. CMS also notes that the lowest-cost catastrophic plan averages nearly 10% cheaper than the next lowest-cost plan at other coverage levels, but catastrophic plans are open only to some applicants, so see HealthCare.gov for who qualifies.

Step 4: Check your doctors and prescriptions before you pick

A plan that looks inexpensive can cost more if your doctor is out of network or your prescription is not covered. Search each plan's provider directory for your doctors and its drug list for your prescriptions before you enroll. If you take a regular prescription, check which tier it sits in, because the same drug can cost a different amount under different plans. For anyone with ongoing care, this check can matter as much as the premium.

Step 5: Enroll by the deadline that fits your start date

If you need coverage on January 1, 2027, enroll by December 15, 2026 and pay the first premium. If January 1 does not matter to you, you can enroll through January 15, 2027, and coverage starts February 1. Either way, avoid waiting for the last day, because a failed payment or a missing document leaves little time to fix it. HealthCare.gov lists the current call center number and local help options, so see the official site if you want someone to walk through the form with you.

Choosing Order

1. Confirm which Marketplace your state uses, so you follow the right dates.
2. Gather your 2027 income estimate and household details, then compare plans by premium plus deductible and out-of-pocket costs, checking doctors and prescriptions.
3. Enroll by December 15 for a January 1 start, or by January 15 at the latest, and pay the first premium so coverage actually begins.

Before You Enroll

• Write down December 15, 2026 if you need coverage on January 1, and January 15, 2027 as the last day to enroll in open enrollment.
• Confirm whether your state uses HealthCare.gov or its own Marketplace, and use that site's dates.
• Estimate your 2027 income for the savings calculation, not last year's income.
• Check that your doctors and prescriptions are covered under the plan you pick.
• Pay the first premium: enrollment without payment does not start coverage.
• Keep the confirmation and the plan documents, and note the date your coverage starts.
• Medicare has its own separate enrollment period, so see Medicare.gov if that applies to you.

This article is for general information, not financial advice.

Sources

• Centers for Medicare and Medicaid Services, Plan Year 2027 Marketplace Plans and Prices Fact Sheet
• HealthCare.gov, Key Dates and Deadlines