Final answer:
The maximum waiting period under Medicare Supplement insurance for pre-existing conditions is 6 months, but this can be reduced or waived if the insured had previous credible coverage.
Step-by-step explanation:
Under Medicare Supplement insurance, commonly known as Medigap, the maximum waiting period before coverage can begin for pre-existing conditions is 6 months. This means that coverage for expenses related to pre-existing conditions can be delayed by the insurance company for up to six months after the policy starts. However, if you had credible coverage before buying a Medigap policy and did not have a break in coverage for more than 63 days, the waiting period could be reduced or waived based on the length of your previous coverage.