Original Medicare plus Medigap usually means higher monthly premiums but low, predictable bills and any doctor in the U.S. who takes Medicare. Medicare Advantage often has low or $0 plan premiums and extras like dental, but uses networks and prior authorization and makes you pay copays up to a yearly cap ($9,250 in-network maximum in 2026).
Key facts: You can't have both: insurers generally can't sell you a Medigap policy while you're in a Medicare Advantage plan. · Original Medicare alone has no yearly out-of-pocket limit; Medicare Advantage plans must have one, averaging $5,421 in-network in 2026, per KFF. · Medicare Open Enrollment runs October 15 to December 7, but switching back to Medigap later can mean medical underwriting and a possible denial.
Let's face it: picking between Medigap and Medicare Advantage is like choosing between an all-inclusive resort and a cruise with a $0 ticket. One charges you at the door. The other charges you at the bar, the spa and the shore excursion, but promises the tab stops somewhere.
Neither is a scam, and neither is a miracle. They're two different ways of splitting the bill, and Medicare Open Enrollment (October 15 to December 7, per Medicare's Choosing a Medigap Policy guide) is when most people pick a lane.
First, Know the Two Roads (Spoiler: You Can't Drive Both)
Road one: Original Medicare (Parts A and B), usually plus a separate Part D drug plan, plus a Medigap policy from a private insurer that pays some or all of your coinsurance and deductibles. For the letter everyone talks about, see our Medigap Plan G explainer.
Road two: Medicare Advantage, a private plan that contracts with Medicare to provide your Part A and B benefits. KFF notes most of these plans also include drug coverage.
And no, you can't combine them. Medicare.gov says you can't buy Medigap to cover your costs in a Medicare Advantage plan. Monogamy, enforced by Medicare rules.
The Money: Pay at the Door or Pay at the Bar (Both Accept Cards)
Everyone on either road still pays the Part B premium, which is $202.90 a month for most people in 2026, per KFF. After that, the roads split hard.
Medigap's deal: a real monthly premium. KFF reports the average Medigap premium among current policyholders was $217 a month in 2023, and it can rise with age and varies a lot by state and plan. Add a stand-alone Part D plan, which averaged $36 a month in 2026.
Medicare Advantage's deal: cheap at the door. KFF says 75% of Medicare Advantage drug-plan enrollees pay no extra plan premium, and the average is $15 a month in 2026. Instead, you pay copays and coinsurance as you use care, and those vary wildly from plan to plan.
The plot twist is the ceiling. Original Medicare has no yearly limit on your out-of-pocket costs unless you add supplemental coverage like Medigap, per Medicare.gov. Medicare Advantage plans must have a cap: no more than $9,250 for in-network care in 2026 (or $13,900 combined for plans with out-of-network coverage), per KFF, which puts the average in-network limit at $5,421. A cap is great. A $5,000 cap is also $5,000.
Doctors and Permission Slips (Who's on the Guest List?)
Original Medicare lets you see any doctor or hospital in the U.S. that takes Medicare, and in most cases you don't need a referral to see a specialist, per Medicare.gov. Medigap rides along wherever Original Medicare goes.
Medicare Advantage may require you to use the plan's network for non-emergency care, may require referrals, and may require prior authorization before it covers certain services, per the same Medicare.gov comparison. Some plans cover out-of-network care at a higher cost.
If your favorite specialist is out of network, that's not a footnote. That's the whole decision.
Extras, Drugs and Vacations (The Goodie Bag Round)
- Drug coverage: most Medicare Advantage plans include Part D. Medigap plans sold after 2005 don't, per Medicare.gov. (BYO pharmacy plan.)
- Dental, vision, hearing: Original Medicare doesn't cover most dental care or routine eye exams. Many Advantage plans offer some of these extras, though KFF notes coverage, caps and networks vary widely. (Read the goodie bag's label.)
- Drug costs either way: Part D out-of-pocket spending is capped at $2,100 in 2026, per KFF. (Finally, a ceiling nobody argues about.)
- Travel abroad: Original Medicare generally doesn't cover care outside the U.S., and some Medigap policies cover foreign travel emergencies. Some Advantage plans offer an emergency travel benefit too, per Medicare.gov. (Check before the cruise, not during.)
The Honest Scorecard (Swipe Right, Swipe Left)
Medigap's legit upsides: predictable bills, any Medicare doctor nationwide, few permission slips. Downsides: a monthly premium that can climb, plus a separate drug plan, and no dental or vision.
Medicare Advantage's legit upsides: low or $0 premiums for many plans, a built-in yearly cap, drug coverage and extras in one card. Downsides: networks, referrals, prior authorization, and copays that can add up toward that cap in a bad health year.
The Fine Print: Leaving Medicare Advantage for Original Medicare is easy. Getting Medigap back is not guaranteed. Your Medigap Open Enrollment Period is a one-time, 6-month window that starts when you have Part B and are 65 or older. Outside it, an insurer may deny you a policy if you don't meet its medical underwriting rules, unless you have a guaranteed issue right. Source: Choosing a Medigap Policy. Our guide to leaving Medicare Advantage covers the exceptions.
The guide also warns the reverse: if you drop Medigap to join Medicare Advantage, you may not be able to get the same policy back. U-turns are permitted. They're just not free.
The Bottom Line (Pick Your Pain, Not Your Neighbor's)
Medigap is pay now, sleep well later. Medicare Advantage is pay less now, maybe pay more later, with a ceiling. The right road depends on your budget, your doctors, your prescriptions, how often you travel and how healthy you expect to be.
Your one move before December 7: list your doctors and prescriptions, then call your local SHIP (State Health Insurance Assistance Program), which the Choosing guide describes as a state program giving free, local health insurance counseling to people with Medicare. Bring the list. They'll do the boring math with you.
Now go choose your road, and may your copays be smaller than a cruise-ship cocktail.
This is general education with a side of sarcasm, not insurance, legal, tax or financial advice, and we don't recommend any insurer or plan. Rules and costs vary by plan and state, and your plan documents beat this article every time. No cruise ships were boarded in the making of this post, though the buffet was thoroughly researched.
Sources:
- Medicare.gov: Compare Original Medicare & Medicare Advantage
- CMS/NAIC: Choosing a Medigap Policy (PDF)
- KFF: How Much Do People with Medicare Pay for Coverage? (Oct. 9, 2026)
- Medicare.gov: Learn what Medigap covers
- SHIP (State Health Insurance Assistance Program)
Frequently asked questions
Can I have Medigap and Medicare Advantage at the same time?
No. Medicare.gov says you can't buy Medigap to cover your out-of-pocket costs in a Medicare Advantage plan, and the Choosing a Medigap Policy guide says insurers generally can't sell you a Medigap policy if you have Medicare Advantage.
Which one covers prescription drugs?
Most Medicare Advantage plans include Part D drug coverage. Medigap plans sold after 2005 don't include drug coverage, so people with Original Medicare and Medigap usually join a separate Part D plan.
When can I switch between them?
During Medicare Open Enrollment, October 15 to December 7, with changes starting January 1. Moving back to Original Medicare is simple, but buying a Medigap policy outside your one-time Medigap Open Enrollment Period can involve medical underwriting unless you have a guaranteed issue right.
