How to Add a Newborn to Your Health Insurance

On this page

• Marketplace plans: 60 days, backdated to birth
• Job-based plans: at least 30 days, also backdated
• Medicaid’s automatic coverage for newborns
• Some states add automatic short-term coverage too
• What it costs to add a child
• Practical steps and deadlines
• Frequently asked questions

Marketplace plans: 60 days, backdated to birth

HealthCare.gov’s rule for a new baby is direct: your coverage “can start the day of the event – even if you enroll in the plan up to 60 days afterward.” Report the birth through your Marketplace account as soon as you can, adding the baby as a household member; this also updates your household size for premium tax credit purposes.

The Marketplace generally asks for a Social Security number for everyone applying for coverage. If your newborn’s SSN hasn’t arrived yet, call the Marketplace call center for guidance on how to proceed with your specific application rather than guessing.

Job-based plans: at least 30 days, also backdated

Federal law (HIPAA’s special enrollment rules) requires an employer plan to let you enroll a newborn within 30 days of birth, and coverage is “effective retroactive to the date of birth.” A newborn added within that window also can’t be treated as a late enrollee or excluded for a pre-existing condition. Contact your employer’s HR or benefits team as soon as you can after the birth rather than waiting for the deadline.

Medicaid’s automatic coverage for newborns

If the mother was enrolled in Medicaid, including retroactive Medicaid coverage, or in CHIP as a “targeted low-income pregnant woman,” at the time of birth, the baby is automatically deemed eligible for Medicaid from the date of birth through their first birthday. No separate application is required. Coverage only ends early if the child dies, the family moves out of state, or the family asks to end it voluntarily. The mother’s Medicaid ID typically covers the baby’s early claims until the state issues the child a separate ID.

CHIP has a similar rule: infants born to a mother covered as a “targeted low-income” pregnant woman are automatically deemed eligible for Medicaid or CHIP without an application, and some states extend the same automatic deeming to babies born to mothers who were themselves covered as low-income children under CHIP.

Some states add automatic short-term coverage too

Some states separately require insurers to cover a newborn under a parent’s policy automatically for a short initial period, but you still have to formally add the child as a dependent, and often pay any added premium, before that window closes. New Hampshire’s rule is a confirmed example: it requires automatic coverage for a newborn for the first 31 days after birth, after which the parent must enroll the child as a permanent dependent to keep coverage going. The exact window varies by state, so check with your insurer or your state’s insurance department rather than assuming a specific number of days.

What it costs to add a child

Adding a child adds that child’s own premium to your plan. On a job-based plan, it may also move you from employee-only coverage to a family coverage tier. Under the standard ACA age curve, a child costs less to insure than an adult, and only the three oldest children under 21 in a family are charged. Additional children are covered at no extra premium. On the cost-sharing side, ACA-compliant family plans must have an embedded individual out-of-pocket maximum, so no single family member, including a newborn, has to spend more than the individual maximum before that person’s own costs are covered in full, even if the rest of the family hasn’t met the family deductible yet. See what an out-of-pocket maximum is and how much health insurance costs for a family of 4.

Practical steps and deadlines

• Report the birth to your Marketplace account, your employer’s HR team, or your Medicaid caseworker as soon as you can, rather than waiting until close to the 60- or 30-day deadline.
• If you’re on Medicaid, confirm with your caseworker that your baby is on file, even though no separate application is required for the first year.
• If you’re on a Marketplace or job-based plan, gather the birth certificate or hospital discharge paperwork, and ask how to handle enrollment if the Social Security number hasn’t come through yet.
• Ask your insurer or state insurance department whether automatic short-term newborn coverage applies where you live, and note the date you need to formally add the child by.

For related life events and how they affect coverage, see qualifying life events for health insurance and covering all family members under the same policy.

Compare family plan prices once your household has changed: compare quotes by ZIP code.

Frequently asked questions

How long do I have to add a newborn to my health insurance?

60 days on a Marketplace plan, and at least 30 days on a job-based plan. Report the birth as soon as you can rather than waiting for the deadline.

Is coverage backdated to the birth date?

Yes, on both Marketplace and job-based plans, coverage for the baby applies retroactively to the date of birth once you enroll within the window.

Do I need to apply for Medicaid separately for my newborn if I’m already on Medicaid?

No. If you were enrolled in Medicaid when your baby was born, the baby is automatically covered for the first year without a separate application.

Will adding my baby raise my premium?

Usually, yes. Your plan adds the child’s premium (or moves you to a family tier on a job-based plan), though children generally cost less to insure than adults under the ACA’s age rules, and only the three oldest children under 21 are charged.

This article is general information, not insurance or legal advice. Exact newborn coverage rules can vary by state, insurer and plan type. Last reviewed September 2026.