It depends. If your parent claims you as a dependent when he or she files taxes, you will be considered part of your parent’s household when applying for premium tax credits and the Marketplace will consider whether the employer plan available to you is affordable and meets minimum value. However, if you are not claimed as a dependent on your parent’s tax filings and instead file your own taxes, you have the choice to enroll in your parent’s employer plan or apply on your own for coverage in the Marketplace with premium tax credits. If this is the case, you should compare your costs under the employer plan to those under a Marketplace plan (potentially with premium tax subsidies, if you qualify) to determine which plan is better for you. (45 C.F.R. § 147.120; 26 C.F.R. 1.36B-2).
On Private Health Insurance Coverage & The Health Insurance Marketplace