Common Mistakes About the ACA Special Enrollment Period (SEP) and How to Avoid Them
The Special Enrollment Period (SEP) under the Affordable Care Act (ACA) is a critical option that allows individuals to enroll in a health insurance plan outside the annual Open Enrollment Period when they experience a qualifying life event. However, SEP is also one of the most misunderstood aspects of ACA coverage.
Many people lose their opportunity to enroll due to incorrect assumptions, missed deadlines, or lack of clear guidance. These mistakes can result in months without health insurance, unexpected medical bills, or financial stress.
This guide breaks down the most common mistakes about the ACA Special Enrollment Period, explains why they happen, and shows you how to avoid them so you can protect your health coverage.
What Is the ACA Special Enrollment Period (SEP)?
Before addressing common mistakes, it’s important to understand what SEP actually is. A Special Enrollment Period is a limited window of time that allows you to enroll in or change a Marketplace health insurance plan outside Open Enrollment.
SEPs are triggered only by specific Qualifying Life Events (QLEs), such as losing coverage, getting married, or moving. They are not automatic and must follow strict federal rules.
Mistake #1: Thinking Any Life Change Qualifies for a SEP
One of the most frequent misunderstandings is believing that any personal change allows you to enroll during a SEP.
Examples that do NOT qualify:
Deciding your current plan is too expensive
Wanting better benefits or a different insurance company
Forgetting to enroll during Open Enrollment
Losing coverage because you stopped paying premiums
Only specific, ACA-defined life events qualify. Assuming otherwise often leads to missed opportunities.
Mistake #2: Not Knowing What Qualifying Life Events Are
Some people actually experience a qualifying event but don’t realize it qualifies for a SEP, so they fail to act.
Common qualifying events include:
Losing employer-sponsored health insurance
Marriage
Divorce that results in loss of coverage
Birth or adoption of a child
Moving to a new coverage area
Gaining lawful immigration status
Losing Medicaid or CHIP eligibility
Not recognizing these events can leave individuals uninsured unnecessarily.
Mistake #3: Believing SEP Is Available All Year
Another common error is thinking that once a qualifying event happens, you can enroll at any time.
In reality:
Most SEPs last 60 days after the qualifying event
Some allow 60 days before the event, such as a scheduled loss of coverage
Missing this window usually means waiting until the next Open Enrollment Period.
Mistake #4: Failing to Report the Event to the Marketplace
SEPs do not activate automatically. You must report your qualifying life event through Healthcare.gov or your state Marketplace.
Many people assume:
The system will update automatically
Their insurance company will notify the Marketplace
Their agent will report the event without confirmation
None of these happen unless the consumer takes action.
Mistake #5: Not Submitting Required Documentation
In many cases, the Marketplace requires proof of your qualifying life event. A common mistake is not submitting documents or submitting them late.
Common documentation includes:
Employer termination letters
Proof of coverage loss
Marriage or divorce certificates
Proof of new address
Immigration documents
Failure to provide documentation can result in SEP denial.
Mistake #6: Assuming Coverage Starts Immediately
Some people believe their coverage begins the same day they enroll or the day the life event occurs.
In most cases:
Coverage starts on the first day of the following month
Only specific events, like birth or adoption, allow retroactive coverage
Misunderstanding start dates can lead to unexpected medical bills.
Mistake #7: Believing Subsidies Don’t Apply During SEP
A common myth is that financial assistance is only available during Open Enrollment.
In reality:
Premium tax credits (APTC) apply during SEP
Cost-sharing reductions (CSR) still apply if eligible
Income rules remain the same
Failing to apply subsidies can result in overpaying for coverage.
Mistake #8: Changing Information to “Force” SEP Eligibility
Some individuals attempt to change income, address, or household information to artificially trigger a SEP.
This is a serious mistake because it may:
Lead to coverage cancellation
Cause major tax adjustments
Be considered Marketplace fraud
All reported information must be truthful and verifiable.
Mistake #9: Not Paying the First Premium on Time
Even if your SEP is approved, coverage does not begin until the first premium—often called the binder payment—is paid.
Common errors include:
Assuming subsidies cover the full premium
Waiting for the insurance card before paying
Not confirming payment with the insurer
Without this payment, the plan can be canceled.
Mistake #10: Not Seeking Professional Help
Many SEP issues occur simply because the process can be confusing. Trying to navigate it alone increases the risk of mistakes.
Not seeking help can result in:
Choosing the wrong plan
Missing enrollment deadlines
Paying more than necessary
Losing coverage entirely
Certified agents and Marketplace navigators are trained to assist at no additional cost.
How to Avoid These SEP Mistakes
To reduce the risk of errors during a Special Enrollment Period:
Act immediately after a qualifying event
Confirm whether your event qualifies
Keep all relevant documentation
Track deadlines carefully
Verify your coverage start date
Work with a certified professional
Preparation and accuracy are key.
