Medicare Supplement Plan D: Coverage, Costs, Pros & Cons

Medicare Supplement Plan D is a standardized Medigap policy sold by private insurers to fill cost gaps in Original Medicare. Plan D covers the $1,736 Part A deductible, skilled nursing facility co-insurance and full 20% Part B co-insurance. But it doesn't pay the $283 Part B deductible or cover Part B excess charges, per CMS. 

Plan D is open to anyone who qualifies for Medicare and is enrolled in Medicare Part A and Part B. Private insurers set their own premiums based on location, age and pricing method. Plan D is not available in Massachusetts, Minnesota or Wisconsin, which have their own standardized Medigap structures.

Medicare Supplement Plan D covers seven federally standardized benefits, identical across all insurers that sell it. The plan pays your Part A deductible in full, covers co-insurance for hospital and skilled nursing stays and pays the 20% Part B co-insurance on doctor visits. Plan D also includes emergency care coverage abroad. So you leave most covered visits without a balance to pay.

Plan D leaves five cost categories without coverage. Each gap represents an out-of-pocket expense you pay directly. The Part B deductible and excess charges are the two most likely to affect you in a standard year, so review all five before comparing Plan D against other Medigap plans. 

• Part B deductible ($283 per year in 2026)
• Part B excess charges (up to 15% above the Medicare-approved rate)
• Prescription drugs (requires a separate Medicare prescription drug plan)
• Dental, vision and hearing care
• Long-term care and private nursing

Plan D occupies a mid-tier position among Medigap plans. It costs more than Plan N and Plans K and L but less than Plan G in most markets, and it has no copays where Plan N charges up to $20 per office visit. Plan D's predictable cost structure suits people who want no surprise bills on covered services but aren't willing to pay Plan G or Plan F premiums.

Medicare Supplement Plan D premiums vary by your insurer's pricing method, your age and your location. MoneyGeek's 2026 rate data shows monthly premiums starting at $207 for a 65-year-old under attained age pricing. The pricing method matters beyond the starting rate: attained age plans raise premiums as you get older, while community-rated plans charge the same amount regardless of age.

Medicare Supplement Plan D shares core benefits with Plans F, G and N but differs in what it leaves unpaid. Plan F covers the Part B deductible and excess charges but is only available to people who qualified for Medicare before Jan. 1, 2020. Plan G covers excess charges but not the Part B deductible. Plan N has no excess charge protection and adds copays up to $20 at office visits.

*Plan F available only to those who qualified for Medicare before Jan. 1, 2020.
†Plan N copays: up to $20 per office visit, up to $50 per ER visit not resulting in inpatient admission.

The best time to buy Medicare Supplement Plan D is during your Medigap Open Enrollment Period, a six-month window that starts when you turn 65 and enroll in Medicare Part B. During this window, no insurer can deny you Plan D or charge more because of pre-existing conditions. 

Outside this window, insurers can use medical underwriting and may deny coverage or charge higher premiums. Switching from a Medicare Advantage plan to Medigap may come with a special enrollment period depending on your circumstances.

Medigap Plan D is worth the premium for people who use Medicare services regularly and want no copays on covered visits. Plan D costs more than Plan N and covers less than Plan G. The decision depends on how frequently you use Medicare, whether your providers accept Medicare assignment and how much you value predictable costs over a lower monthly premium.

Medicare Supplement Plan D covers your $1,736 Part A deductible and full co-insurance with no copays. It won't pay your $283 Part B deductible or protect against excess charges. Premiums start at $207 per month at age 65. Plan D makes the most sense when regular care use makes predictable, copay-free costs more valuable than a lower monthly premium.

We've answered the most frequently asked questions about Medicare Supplement Plan D coverage gaps, pricing methods and enrollment window: