No. Medicare Supplement plans sold under the same letter are not the same across the board, but their medical benefits are: federal law requires every insurer selling, say, Plan G to cover the exact same set of services as every other insurer’s Plan G. What changes between carriers is the premium, the pricing method behind that premium, the household and other discounts on offer, and the quality of service you get. So the honest answer to “are all Medicare Supplement plans the same” is that the coverage inside a given letter is standardized, and almost everything else about the policy is not.
Why the Medical Benefits Are Identical
Section 1882 of the Social Security Act directs the federal government to certify Medigap policies that meet minimum standards.1Office of the Law Revision Counsel. 42 USC 1395ss – Certification of Medicare Supplemental Health Insurance Policies Federal regulations implement this by requiring insurers to follow benefit templates based on the National Association of Insurance Commissioners model.2eCFR. 42 CFR Part 403 Subpart B – Medicare Supplemental Policies Every private insurer selling a particular lettered plan has to include the same set of medical benefits.
Pick a Plan G from Company A, and the covered services — the Part A deductible, Part B coinsurance, skilled nursing facility costs, and foreign travel emergencies — are identical to a Plan G from Company B.3Medicare. Compare Medigap Plan Benefits Insurance companies cannot add or remove core medical benefits from these federal templates. That is what makes it reasonable to compare on price and carrier reputation rather than hunt through fine print for hidden gaps.
What Is Identical for a Given Plan Letter
For whichever letter you choose, every carrier must cover the same combination of these Original Medicare out-of-pocket costs:
- Part A coinsurance and hospital costs, including up to 365 additional days after Medicare benefits run out
- The Part A deductible, which is $1,736 per benefit period in 20264Medicare. Costs
- Part B coinsurance, the 20% of outpatient services you pay after the deductible4Medicare. Costs
- The Part B deductible of $283 in 2026, covered only by Plans C and F4Medicare. Costs
- Skilled nursing facility coinsurance
- Foreign travel emergencies
- Part B excess charges, covered only by Plans F and G
Within a letter, two carriers cannot differ on any of these. If one broker tells you their Plan N covers something another broker’s Plan N does not, that claim is wrong on the medical benefits.
What Differs by Plan Letter
Ten standardized Medigap plans are available in most states: A, B, C, D, F, G, K, L, M, and N.3Medicare. Compare Medigap Plan Benefits Each letter covers a different mix of the costs above.
Plan A offers the most basic coverage. Plans F and G are the most comprehensive, and Plan G is the most popular choice for new enrollees, covering everything on the list except the annual Part B deductible.3Medicare. Compare Medigap Plan Benefits Plans K and L pay a percentage of costs rather than the full amount — 50% and 75% respectively — which lowers premiums but raises your spending until you reach the annual out-of-pocket limit.
Plan N sits in the middle, covering most of what Plan G covers but with small copayments: up to $20 for some office visits and up to $50 for emergency room visits that do not lead to a hospital admission.5Centers for Medicare and Medicaid Services. Revised Questions and Answers Regarding Implementation of Medicare Supplement Plan N The emergency room copayment is waived if you are admitted. Plan N does not cover Part B excess charges.
One important eligibility boundary: if you turned 65 on or after January 1, 2020, you cannot buy Plan C or Plan F.3Medicare. Compare Medigap Plan Benefits If you were eligible for Medicare before that date — even if you had not enrolled yet — you may still be able to buy them.6Medicare. When Can I Buy a Medigap Policy? For anyone newly eligible, Plan G is the closest alternative to Plan F, and Plan D mirrors Plan C minus the Part B deductible coverage.
Plans F and G also come in high-deductible versions, which carry lower monthly premiums in exchange for paying all Medicare cost-sharing out of pocket until you reach the annual deductible of $2,950 in 2026, after which the plan covers benefits in full for the rest of the year.7Centers for Medicare & Medicaid Services. F, G and J Deductible Announcements High-deductible Plan G is available to anyone newly eligible for Medicare on or after January 1, 2020.
What Differs Between Carriers
Since the covered services inside a letter are fixed, the real variation between carriers lives in price and the pieces around price.
Pricing Method
Carriers use one of three methods, and the choice shapes what you pay over 20 or 30 years of retirement:
- Community-rated. Everyone pays the same premium regardless of age. A 65-year-old pays the same as an 80-year-old. Premiums can still rise due to inflation or increased medical costs, but not because you got older.
- Issue-age-rated. Your premium is based on your age when you first buy the plan and stays at that tier as you age, though it can still rise for reasons unrelated to your birthday.
- Attained-age-rated. Premiums start lower than other methods but climb as you get older. Over time, these plans often become the most expensive option despite the attractive entry price.
Two carriers offering the same Plan G in the same ZIP code can price it very differently depending on which method they use. A community-rated or issue-age-rated plan may cost more at 65 but save money over the long run compared with an attained-age plan that keeps climbing. Not every carrier in your area uses the same method, so asking about pricing structure is one of the first questions worth asking.
Underlying Premium Factors
Beyond the pricing method, premiums differ because insurers negotiate different provider reimbursement rates, carry different claims experience, and run on different overhead. All Medigap premiums are also subject to general medical inflation. One government analysis found that Medigap premiums rose by an average of roughly 3% to 4% per year over a decade-long period, with older policies seeing somewhat larger annual increases than newer ones.
Discounts and Extras
Many carriers offer household discounts — reduced premiums when two people living at the same address each hold a Medigap policy. These vary by insurer and are not available from every company, so asking about them during shopping can produce meaningful savings for a couple.
Some carriers also offer perks that sit outside the federally required benefits: gym memberships through wellness programs, discounts on dental and vision services, or digital tools for managing your policy and claims. These can add value but should not outweigh premium cost or company reliability.
Financial Strength and Service
Financial strength ratings from agencies such as AM Best indicate whether an insurer has the resources to pay claims reliably over the long term. A carrier with strong ratings is less likely to face financial trouble that could affect coverage decades into retirement. Service quality, claims handling, and the ease of dealing with the company day to day also vary and are worth checking through independent reviews.
Three States That Do Not Use the Standard Letters
If you live in Massachusetts, Minnesota, or Wisconsin, the standard lettered plan system does not apply.8Medicare. Find a Medigap Policy That Works for You These three states established their own standardized Medigap frameworks through state legislation. The goal of filling gaps in Original Medicare is the same, but the benefit groupings and plan names differ from the national A-through-N labels. Plans are organized under categories like Basic and Extended Basic options. Standardization still applies within each state: carriers must offer the same benefits for the same category. Your state insurance department can help you compare the available options.
When You Can Buy at the Same Price Regardless of Health
Because carriers price the same coverage differently, the window in which you can switch freely between them matters. The six-month Medigap Open Enrollment Period begins the first day of the month in which you are both 65 or older and enrolled in Medicare Part B.9Centers for Medicare & Medicaid Services. Timing of the Six-Month Medigap Open Enrollment Period During these six months, every insurance company that sells Medigap in your area must sell you any plan it offers at the standard price, regardless of your health history. The company cannot turn you down or charge you more because of pre-existing conditions.
Once that window closes, the federal protections fall away.6Medicare. When Can I Buy a Medigap Policy? Outside Open Enrollment, insurers can use medical underwriting to review your health, charge higher premiums based on your medical history, or deny coverage entirely. There is no second Open Enrollment Period.
If you apply later, even approval can come with a waiting period of up to six months during which the policy will not pay for services related to conditions you were treated for or diagnosed with before coverage started. That waiting period can be reduced or eliminated if you had at least six months of continuous prior creditable coverage without a gap of more than 63 days.
Certain life events trigger guaranteed issue rights, which require insurers to sell you a Medigap policy without medical underwriting even after Open Enrollment has ended.10Medicare. Buying a Medigap Policy Common qualifying situations include losing employer group health coverage, having your Medicare Advantage plan leave your service area, or your Advantage plan ceasing to operate. You will need to provide proof to the insurance company.
The practical takeaway runs through every section above: once you have settled on the letter that fits your situation, you are comparing identical medical coverage from different companies. Price it carefully, ask how the premium is structured, and check which carriers will still take you at the standard rate on the day you apply.