Who Counts as a Dependent?
In health insurance, a dependent is someone who can be covered under your plan rather than having their own. The rules differ slightly between plan types:
ACA Rules for Dependents
- Children under 26: Must be covered on a parent's plan regardless of marital status, student status, financial independence, or whether they live at home. This is federal law under the ACA.
- Spouse: Legally married spouses qualify. Domestic partners may qualify depending on the plan and state.
- No other relatives: Parents, siblings, grandchildren, and other relatives generally cannot be dependents on your individual plan.
What Happens at 26
Children are removed from a parent's plan on their 26th birthday (or end of that month, depending on the plan). This triggers a qualifying life event giving them 60 days to enroll in their own plan. See our Turning 26 guide.
For marketplace plans: Adding dependents affects your premium and potentially your subsidy. A family of 4 has a higher income threshold for subsidies than an individual. Use your total household size when checking subsidy eligibility.
Dependents on Private vs. Marketplace Plans
Both ACA marketplace plans and private ACA-compliant plans follow the same dependent rules. The under-26 rule applies to both. The only difference is subsidy eligibility — marketplace plans may reduce your premium with dependent children; private plans charge full price.
Related Terms
Last updated: March 30, 2026.
