Medicare Supplement plan L offers basic coverage, but includes some cost sharing. For example, you pay 25% of the cost for several benefits, such as your Medicare Part A deductible or Medicare Part B coinsurance and copayments. Medicare Supplement Plan L, however, has an out of pocket limit after you pay your Medicare Part B deductible. Once you have paid your out-of-pocket limit, your supplement pays 100% of required coverage for the remainder of the calendar year.