Because anyone can now buy coverage regardless of health, the law sets enrollment windows so people do not wait until they are sick. The Open Enrollment Period (OEP) is the recurring yearly window when eligible people may enroll in a qualified health plan, renew, or change plans, with no life change needed (45 CFR §155.410(a)). The limit applies outside Covered California too: California individual plans may be sold only during open, annual and special enrollment periods.
A Special Enrollment Period (SEP) opens when a life change (a "triggering event") happens outside open enrollment. In California, the person has 60 days from the triggering event to apply, both inside and outside the Exchange (§10965.3(d)(2)). Triggering events include:
Loss of minimum essential coverage, such as losing employer coverage after a layoff, but NOT a loss caused by failing to pay premiums on time
Gaining a dependent through birth or adoption
A permanent move that gives access to new health plans
Release from incarceration
A military reservist returning from active duty
Exceptions to remember:
A person losing Medicaid or CHIP coverage (Medi-Cal in California) has 90 days after the triggering event to choose a Covered California plan (45 CFR §155.420(c)(6)).
Medi-Cal itself has no enrollment window; people can apply for it at any time of year.
When SEP coverage starts (outside the Exchange): for a birth, adoption or placement for adoption, on the date of that event, so a newborn has no gap. For marriage, a new registered domestic partner, or a loss of minimum essential coverage, on the first day of the following month (§10965.3(f)(4)).