I’m under 26 and eligible to be covered as a dependent under my mom’s job-based policy. Mom no longer claims me as a tax dependent – I file my own taxes, though my income isn’t very high. If subsidized Marketplace coverage would be even more affordable to me, can I sign up for that instead?

Yes. Although the general rule is that people are not eligible for Marketplace subsidies when they are also eligible for affordable job-based health coverage, a young adult is eligible for premium tax credits in the Marketplace as long as they are not claimed as a tax dependent by their parents. The availability of dependent coverage under your parent’s health plan does not affect your eligibility for premium tax credits in the Marketplace.