What Medicare Supplement coverage does
Medicare Supplement insurance, also called Medigap, works alongside Original Medicare. Depending on the standardized plan letter, it may help pay certain deductibles, coinsurance, or copayments that Original Medicare does not pay.
What it does not include
A Medigap policy generally does not include outpatient prescription drug coverage. It is not the same as Medicare Advantage, and it does not replace Part A or Part B. Routine dental, vision, hearing, and long-term care are generally not covered by Medigap policies.
Why enrollment timing matters
Your six-month Medigap Open Enrollment Period begins when you are 65 or older and enrolled in Part B. During that period, federal protections generally allow you to buy available policies without medical underwriting. Outside protected periods, eligibility and pricing can depend on state law and insurer requirements.
Part D prescription coverage
A standalone Part D plan can be added to Original Medicare. Compare the formulary, drug tiers, preferred pharmacies, deductibles, and expected annual costs—not simply the monthly premium.
Questions to compare
Consider expected medical use, travel, budget, preferred providers, prescriptions, tolerance for changing premiums, and whether you value provider flexibility or bundled extra benefits.