You can remain covered as a dependent on your parent’s policy until the end of the plan year following your 26th birthday. Once you lose eligibility, you will qualify for a special enrollment opportunity due to loss of other coverage.  This will let you apply for health coverage and assistance through the Marketplace, even though it won’t be during a regular Open Enrollment period.

In addition, if your parent’s policy is a group plan offered by an employer with at least 20 workers, you would also be able to continue coverage under the policy through COBRA for up to 3 years.  However, the employer contribution to the premium would likely end and Marketplace subsidies cannot be applied to the COBRA coverage.