Reviewed & Fact-Checked by getCoverageNow Editorial Team
GCN Medical & Insurance Compliance Advisory Group • Updated July 2026
A common misconception is that you can buy health insurance whenever you want. In reality, the United States healthcare system operates on a strict legal buying window called Open Enrollment. Usually, this happens from November 1st to January 15th every year.
Sponsored Resource
Why is there a strict deadline?
The system is designed this way to prevent "adverse selection." If people could buy insurance whenever they wanted, everyone would simply wait until they got cancer or broke a leg to buy a policy. They would get their expensive treatments paid for, and then cancel the policy. This would bankrupt the entire insurance system. The Open Enrollment deadline forces you to buy coverage while you are healthy, pooling risk to subsidize care for the sick.
What if I missed the deadline?
If it is February and you do not have insurance, you are mostly locked out of the ACA Marketplace until next November. You cannot just log on and buy a plan.
Clinical Insight: The Exception
The ONLY way to get comprehensive insurance outside of Open Enrollment is if you trigger a Special Enrollment Period (SEP). This happens if you experience a "Qualifying Life Event"—such as losing your job-based insurance, moving to a new state, getting married, having a baby, or a drastic drop in income. If you trigger an SEP, the government grants you exactly 60 days to buy a plan. If you don't qualify for an SEP, your only backup is risky short-term insurance or a discount medical plan.