Medicare Supplement plans (also called Medigap) fill the financial gaps Original Medicare leaves behind. The trade-off is a higher monthly premium for very low costs when you actually use care — and the ability to see any doctor in the country that accepts Medicare.
Original Medicare (Parts A and B) covers about 80% of your medical costs. The remaining 20% has no annual cap — meaning a single hospital stay or serious illness can run into tens of thousands of dollars out of pocket. A Medicare Supplement plan exists to plug that gap.
When you get a medical bill, Original Medicare pays its 80% share, then automatically forwards the rest to your Medigap insurance company. Your Medigap policy pays its portion — depending on which plan letter you have, that's anywhere from most of the remaining 20% to all of it — and you're left with very little (or nothing) to pay.
There are no networks. There are no referrals. No prior authorization phone calls. If a doctor or hospital accepts Original Medicare — and the vast majority of them in the U.S. do — they'll accept your Medigap. You can travel anywhere in the country and use it.
The simple way to think about it: with a Supplement, you trade a higher monthly premium for very low and very predictable costs when you actually use healthcare. The opposite trade-off from Medicare Advantage.
Medigap covers your medical costs only. It does not include:
This is why many Supplement clients end up with three separate policies: Original Medicare, a Medigap plan, and a Part D prescription plan. It sounds complicated but each piece does one job well, and the combination usually beats an all-in-one Advantage plan for predictability.
Your strongest window to buy a Medigap policy is the six months starting the month you turn 65 and are enrolled in Part B. During this Medigap Open Enrollment Period, carriers cannot turn you down or charge you more based on health history. You get the best rate of your life, period.
Outside that window, in most states, carriers can underwrite (ask health questions) and either deny coverage or charge more. A few states — Connecticut, Massachusetts, Maine, and New York — have year-round guaranteed-issue rules. Most states do not.
On a call, we'll cover:
We do not push any one carrier. The recommendation depends entirely on your zip code, age, gender, tobacco status, and which carriers have the best rate stability over the last 5 years.
Yes. Medigap doesn't use networks. Any doctor or hospital in the country that accepts Original Medicare (which is the vast majority of them) will accept your Medigap plan automatically.
Standardization means every Plan G covers the same things — but carriers can price differently and raise rates differently over time. Some carriers are aggressive on rate increases; others are stable. Picking the right carrier is as important as picking the right plan letter.
Yes — Medigap premiums almost always increase annually (think 3–6% in a typical year, sometimes more). The carrier you pick matters: some have a track record of small, predictable increases. Some don't. We look at that history when we recommend a carrier.
You can apply to switch any time of year, but you'll typically be subject to medical underwriting — meaning the new carrier can ask health questions and potentially deny you. The cleanest strategy is picking a stable carrier the first time.
Different products entirely. A Supplement adds to Original Medicare (you keep Original, plus a Medigap policy, plus a Part D plan). Advantage replaces Original Medicare with a private all-in-one plan that's network-based. We compare both for you on a call so you can decide which model fits.
Side-by-side comparison of the two most popular Medigap plans with real numbers.
Plan PickingPlan F was the gold standard. New members can't buy it. Should you switch?
Plan PickingEvery Plan G has identical benefits. So why do prices vary so much by carrier?
Plan Picking10 states let you switch Medigap yearly without medical underwriting. Is yours one?
CostsFull breakdown of Part B, Part D, Medigap, and total annual cost ranges.
DecisionsThe biggest Medicare decision, explained side by side in plain English.
Book a free 20-minute call. Keith pulls Plan G and Plan N quotes for your specific zip code, walks through the real numbers with you on the screen, and gives an independent recommendation. No fees, no pressure, no obligation.