how-to
7 Steps to Choose a Medicare Supplement Plan
Last Updated: October 24, 2026
Quick Summary
To choose a Medicare Supplement plan, first confirm you are enrolled in Parts A and B and buy during your six-month Medigap Open Enrollment Period, when insurers cannot deny you or charge more for health history. Then compare standardized plan letters, get quotes from several insurers for the same letter, and check drug coverage, insurer ratings, and switching rules.
- Medigap pays Original Medicare costs like deductibles, coinsurance, and copayments but is not a stand-alone plan.
- Plan F is closed to people who became eligible for Medicare after January 1, 2020, so most new enrollees focus on Plan G and Plan N.
- Plan G covers nearly everything except the Part B deductible, while Plan N costs less monthly but adds copayments.
- Medigap does not cover prescription drugs, so you need a separate Part D plan for drug coverage.
- Many insurers offer household discounts commonly ranging from 5% to 12% when a spouse holds a policy with the same carrier.
Table of Contents
- What a Medicare Supplement Plan Actually Covers
- Step 1: Confirm Your Eligibility and Enrollment Window
- Step 2: Compare Plan Letters With a Medigap Plans Comparison Chart
- Step 3: Medicare Supplement Plan G vs. Plan N
- Step 4: Estimate Medicare Supplement Plan Costs
- Step 5: Check Prescription Drug and Ancillary Coverage
- Step 6: Verify the Insurer, Service Area, and Switching Rules
- Get a Personal Plan Comparison From Your Medicare Agent
- Frequently Asked Questions
What a Medicare Supplement Plan Actually Covers
A Medicare Supplement plan, often called Medigap, is private insurance that pays some of the costs Original Medicare leaves behind (What's Medicare Supplement Insurance (Medigap)?).
At Your Medicare Agent Medicarehelpinfl, we explain this distinction constantly because it trips people up. Medigap is not a stand-alone health plan.
The core benefit is predictable cost sharing. Instead of facing a coinsurance bill after a hospital stay, you know your plan will pick up its share.
Step 1: Confirm Your Eligibility and Enrollment Window
You can buy a Medigap policy once you are enrolled in Medicare Part A and Part B. Your best window is the Medicare Supplement Open Enrollment Period, a six-month span that starts the first month you are 65 or older and enrolled in Part B (When can I buy a Medigap policy?).
During this window, insurers must sell you a policy regardless of your health history. They cannot charge you more or deny you because of a pre-existing condition. Miss it, and medical underwriting can apply in most states.
Before you shop for a plan, confirm exactly when your window opens. Our guide to the Medicare Initial Enrollment Period walks through the dates that determine when you can first buy coverage.
Step 2: Compare Plan Letters With a Medigap Plans Comparison Chart
Medigap policies come in standardized plan letters, labeled A through N. Federal rules require every insurer to offer the same basic benefits under each letter, so a Plan G from one company covers the same core items as a Plan G from another (Get Medigap Basics).
Every plan covers Part A hospital coinsurance and hospital costs for an extra period, Part B coinsurance, the first few pints of blood, and Part A hospice care coinsurance. The letters differ in what else they add.
| Plan Letter | Part B Deductible | Part B Excess Charges | Skilled Nursing Coinsurance | Foreign Travel Emergency |
|---|---|---|---|---|
| Plan A | No | No | No | No |
| Plan B | No | No | Yes | No |
| Plan F | Yes | Yes | Yes | Yes |
| Plan G | No | Yes | Yes | Yes |
| Plan N | No | No | Yes | Yes |
Plan F is closed to people who became eligible for Medicare after January 1, 2020, so most new enrollees focus on Plan G and Plan N.
Step 3: Medicare Supplement Plan G vs. Plan N
The choice between Plan G and Plan N comes down to how you want to pay.
Plan G covers nearly everything Original Medicare leaves behind, except the Part B deductible, which you pay once per year.
Plan N costs less each month but asks more at the point of care.
Here is the honest trade-off. If you see specialists often or want the simplest possible billing, Plan G usually wins.
Step 4: Estimate Medicare Supplement Plan Costs
Monthly premiums vary widely by insurer, plan letter, age, tobacco use, household status, and where you live, so no single number applies to everyone. Pricing depends on the carrier, your ZIP code, and the pricing method the insurer uses. We recommend gathering quotes from several insurers for the same plan letter before deciding, the spread between the cheapest and most expensive carrier for an identical Plan G in the same ZIP code is often large enough to change the decision.
The Four Factors That Move Your Premium
- Plan letter. Plan G and Plan F carry the richest benefits and the highest premiums. Plan N and Plan A cost less because you absorb more at the point of care. Higher-letter plans are not automatically better, they are better only if the extra coverage is worth more to you than the premium difference.
- Pricing method. Community-rated, issue-age-rated, and attained-age-rated plans behave very differently over time (see below).
- Age and tobacco status. Most carriers charge more as you age and apply a tobacco surcharge. Quitting before you apply can lower your rate, and some carriers re-rate after a set period of non-use.
- Household discount. Many insurers offer a discount, commonly in the range of 5% to 12%, when a spouse or household member also holds a policy with the same carrier. Ask specifically; it is rarely volunteered.
Pricing Methods and Long-Term Premium Increases
Insurers price Medigap policies in three main ways:
- Community-rated (no-age-rated). Everyone in the pool pays the same premium regardless of age. Your rate can still rise for inflation or claims experience, but not because you got older.
- Issue-age-rated. Your premium is set based on your age when you buy and does not increase solely because you age. Buying earlier locks in a lower age band.
- Attained-age-rated. Your premium rises as you get older, typically in steps. It often starts cheapest and climbs the most over a 20- to 30-year retirement.
That difference matters over decades. A plan that looks $40 a month cheaper at 65 can cost more by 80 once attained-age increases compound. Ask each insurer which method it uses, and expect modest annual increases across the board from medical inflation and claims trend. Budget for premiums that rise over time rather than staying flat.
A Worked Example: Plan G vs. Plan N Over One Year
Numbers below are illustrative only, substitute your own quotes, but the structure is how to compare.
| Cost item | Plan G (example) | Plan N (example) |
|---|---|---|
| Monthly premium | $150 | $115 |
| Annual premiums | $1,800 | $1,380 |
| Part B deductible (you pay) | $257 | $257 |
| Part B copays (office/ER visits) | $0 | ~$20 per office visit, up to $50 per ER visit (waived if admitted) |
| Part B excess charges | Covered | Not covered |
| Estimated annual out-of-pocket (light year, ~4 office visits) | ~$2,057 | ~$1,717 |
| Estimated annual out-of-pocket (heavy year, ~20 visits + 1 ER) | ~$2,057 | ~$2,087+ |
The takeaway: Plan N usually wins in a light year and can lose in a heavy year. Plan G costs more up front but caps your exposure. Run your own visit estimate through this table before choosing.
If you are weighing whether the monthly cost is justified, our look at whether Medigap is worth it helps you compare premiums against the bills you would otherwise face.
Step 5: Check Prescription Drug and Ancillary Coverage
Medigap does not cover prescription drugs. That surprises many people, and it is one of the most common gaps we see.
The same rule applies to dental, vision, and hearing. Standardized Medigap benefits do not include them, though some insurers sell separate ancillary products.
For a full explanation of what is and is not covered, read our guide on whether Medigap covers prescription drugs.
Step 6: Verify the Insurer, Service Area, and Switching Rules
A plan letter is standardized, but the company behind it is not. Before you sign, check four things about the insurer: its financial strength rating (AM Best and similar raters publish these), its complaint record (state insurance department complaint indexes are public), its rate history (ask for approved increases over the last several years), and whether the plan is actually sold in your ZIP code.
When You Can Switch Without Medical Underwriting
Outside your six-month Medigap Open Enrollment Period, a new insurer can generally use medical underwriting and decline you or charge more. But there are protected windows where you can switch with guaranteed issue, no health questions. Common federal triggers include:
- Your Medicare Advantage plan leaves the network or exits your area.
- Your Medicare Advantage plan reduces benefits or raises cost sharing above a set threshold.
- You move out of your plan's service area.
These windows are time-limited, often 63 days, so confirm the exact deadline before you act.
State Rules That Change the Math
A handful of states add protections beyond federal rules. The best known are the birthday rules in states such as California, Oregon, Missouri, and Illinois, which give residents a window around their birthday each year to switch to a Medigap plan of equal or lesser benefit without underwriting. A few states also guarantee issue for certain plan changes or after a set number of years on a plan.
A Switching Decision Framework
Use this sequence before you cancel an existing policy:
- Confirm you have a guaranteed-issue right. If yes, you can shop freely within the window. If no, assume underwriting applies.
- Apply to the new insurer first. Do not cancel the old policy until the new one is approved and you have the effective date in writing.
- Check the new plan's network and drug fit. A cheaper premium is not a saving if your doctors or prescriptions fall out of the plan.
- Time the transition. Overlap the old and new policies by at least a month so you are never uninsured.
- Keep proof of continuous coverage. It matters if a future guaranteed-issue right depends on your coverage history.
Our guide on what happens if you drop Medigap covers the consequences of changing coverage in more detail.
Get a Personal Plan Comparison From Your Medicare Agent
Comparing plan letters is straightforward. Matching a letter to your doctors, your prescriptions, and your budget is where most people get stuck. That is the work we do at Your Medicare Agent Medicarehelpinfl.
If you would rather hand the comparison to someone who does it daily, learn how to find a Medicare agent you can trust, then get a personal comparison built around your health needs and budget.
Frequently Asked Questions
How do I compare Medicare Supplement plans side by side?
Start with the plan letter, because Medicare Supplement plans are standardized: a Plan G from one insurance company covers the same benefits as a Plan G from another. The differences come down to monthly premium, the insurer's pricing method, customer service, and any extra perks. Build a Medigap plans comparison chart with columns for plan letter, premium, deductible, and out-of-pocket costs, then narrow it to two or three letters that fit your budget and how often you see specialists.
Which Medicare Supplement plan offers the most coverage?
Plan F and Plan G offer the fullest coverage of medical expenses, including the Part B deductible for Plan F. Plan F is closed to anyone who became eligible for Medicare on or after January 1, 2020, so most newly eligible people look at Plan G instead. Plan G leaves you responsible for the Part B deductible but covers the remaining coinsurance and hospital costs. Confirm current benefit details on Medicare.gov before you decide.
What should I consider when choosing a Medigap plan?
Weigh four things: your monthly premium budget, how often you use doctors and hospitals, whether you need prescription drug coverage (which Medigap does not include), and whether you can switch later without medical underwriting. If you have ongoing specialists or travel abroad, a higher-coverage letter like Plan G may cost more per month but reduce surprise out-of-pocket costs. Ask each insurer how it prices premiums, since attained-age pricing rises as you get older.
Can I switch Medicare Supplement plans after I enroll?
Yes, but outside your Medigap Open Enrollment Period, an insurer can use medical underwriting to review your health history and may decline your application or charge more. Guaranteed-issue rights apply in specific situations, such as losing employer coverage or moving out of a plan's service area. If you are considering a switch, compare quotes and confirm your guaranteed-issue eligibility before canceling your current policy so you do not create a coverage gap.
Choosing a Medicare Supplement plan is not about finding the cheapest premium. It is about matching a plan letter to your health, your doctors, and your tolerance for out-of-pocket costs, then confirming the timing so you keep your guaranteed-issue rights. Get started with Your Medicare Agent Medicarehelpinfl and compare plans with clear guidance on eligibility, enrollment windows, and coverage gaps.
