For the millions of Americans who receive health insurance through their employer, the thought of losing their job—and their health insurance coverage—is an extremely distressing fear. A federal law known as the Consolidated Omnibus Budget Reconciliation Act of 1985, or COBRA, enables individuals who lose their employment-based group health coverage because they have lost their job (and for certain other reasons, known as “qualifying events”) to continue that coverage, at a cost, for a temporary period of time. The following Q&A provides a primer on the basics of COBRA continuation coverage.

Who is eligible?

Under COBRA, group health plans sponsored by employers with 20 or more employees generally are required to offer employees and their dependents an extension of group health insurance coverage after a job loss. (If you have lost your job due to “gross misconduct,” your employer is not required to offer you COBRA coverage. Gross misconduct entails extremely wrongful actions on the part of an employee, such as those that are wanton, willful or reckless.) The law does not cover the District of Columbia, federal employees, particular church-related programs and most companies with fewer than 20 employees (although continuation might be available at the state level for small businesses).

However, if your employer drops all of its health plans, or goes out of business, it no longer has the obligation to continue your COBRA coverage. Additionally, if you move outside of the designated coverage area of your health plan, you can lose COBRA benefits.

When does coverage go into effect?

If you are eligible for COBRA and lose your job either voluntarily or involuntarily, you may extend your coverage for yourself and your dependents for up to 18 months. An employer also can be required to offer COBRA coverage in situations other than a job loss. For example, if you become eligible for Medicare or you get divorced or legally separated, your spouse and dependent children can receive up to 36 months of continued health insurance coverage. Your dependent children also can receive up to 36 months of coverage if they lose dependent-child status on your health insurance plan.

You also may receive 29 months of COBRA coverage if you are qualified for Social Security disability benefits, lose your job and meet other specific requirements.

How much does it cost?

COBRA requires an employer to make an offer of continuation coverage; it does not require the employer to pay for it, or to contribute to it on the same basis as it did when you had the coverage as an active employee. If you want COBRA coverage, your employer can require that you pay 100% of what the coverage costs (in other words, both the premium you had paid as an active employee, plus any share of the premium that your employer may have paid). In addition, your employer can require that you pay an additional 2% in administrative costs. COBRA premiums can be extremely expensive for someone who is unemployed, but because the premium is calculated on a group policy, it may be less expensive than a premium on an individual policy especially for individuals with pre-existing conditions.

What if I don’t want COBRA coverage?

If you are eligible to receive COBRA coverage after losing your job, you may be thinking about turning down the coverage. Maybe you think it’s too pricey and you’re planning on finding a new job with health insurance very soon. However, you may want to reconsider.

Here’s why: Unless you have a firm job offer in hand, it can take you longer than you think to find new employment and when you do, there may be a waiting period before you are eligible for your new employer’s health benefits. In the meantime, you will be without health coverage and if you have an accident or are diagnosed with a serious illness, you may find yourself in quite a bind.

Furthermore, if you have a gap in insurance coverage longer than 63 days, you will lose your health insurance rights under HIPAA (the Health Insurance Portability and Accountability Act of 1996). This federal law guarantees that people with continuous health coverage cannot be denied health insurance even if they have a pre-existing condition. However, if your gap in coverage exceeds 63 days and you either already have a pre-existing condition or are diagnosed with a condition, you may have a hard time finding an insurer to cover you. Therefore, it may be best to accept COBRA coverage until you can find a new job with health benefits.

What if my company doesn’t offer COBRA?

If you work for a smaller company that does not offer COBRA, you still may have “COBRA-like” rights through your state. Many states have implemented their own COBRA laws that offer employees at smaller companies the opportunity to purchase COBRA coverage.

Where can I learn more?

As a federal law, COBRA falls under the Department of Labor’s jurisdiction. If you have questions about COBRA or grievances to report, you should contact your regional office of the Pension and Welfare Benefits Administration of the U.S. Department of Labor.