Under a Federal law passed in 1997, no insurer or HMO may impose a preexisting condition limitation unless you had a break in coverage for 63 days or more. For instance, if you terminated health coverage under policy X as of June 30th, as long as you become covered under another policy within 63 days of such termination, the new policy cannot exclude any preexisting conditions.
For purposes of this new law, coverage under COBRA counts as continuous coverage. Therefore, you must obtain new health coverage within 63 days after the end of your COBRA continuation coverage. If you do not, a new policy can exclude preexisting conditions. Under the law, your insurer is required to give you a certificate which verifies that you were covered under their policy. This must be provided to you when your health coverage under the policy ceases.
In the event that you do have a break in health coverage, there are limitations on the nature of preexisting condition provisions. These provisions may only exclude a condition for a period of not more than 12 months. In addition, they can only exclude conditions for which medical advice, diagnosis, care, or treatment was recommended or received within the 6-month period prior to your enrollment in the new policy.