(stop loss) amount over which a health insurance plan pays 100% of the costs in a percentage participation plan. Here, an insured shares costs with the insurer according to some predetermined ratio. For example, an insured may pay 20% of covered costs and the insurer 80%. However, most group medical plans pick up all covered expenses over a certain deductible amount or specified dollar limit. For example, once the insured has paid a $2000 deductible amount, the plan may pay 100% of covered expenses for the remainder of the policy year.