This article is educational and not insurance, tax, or medical advice; unless a different year is noted inline, all figures reflect the 2026 plan year as published by CMS, MedPAC, and KFF.
TL;DR — Quick Verdict
- Premium is the smallest variable. In 2026, 75% of enrollees in individual Medicare Advantage plans with drug coverage pay nothing beyond the $202.90 Part B premium, according to KFF — which means premium tells you almost nothing about which plan is cheaper.
- The out-of-pocket limit is where the real money sits. The 2026 federal ceiling is $9,250 in-network, but the enrollment-weighted average is $5,421 — a $3,829 spread between an average plan and a worst-case plan.
- HMO versus PPO changes the math twice: HMOs average a $4,636 in-network out-of-pocket limit and $12 monthly supplemental premium; PPOs average $6,592 in-network and $18 monthly.
- Prior authorization is a cost factor, not a paperwork factor. 99% of Advantage enrollees are in plans requiring it, and insurers denied roughly 8% of the nearly 53 million requests they processed in 2024 (KFF).
- The “money back in your Social Security check” pitch is usually small: among the 6.7 million enrollees in plans offering a Part B rebate, 39% get under $10 a month.
- Recommendation: rank plans by out-of-pocket limit, specialist coinsurance, drug tier placement, and prior-authorization scope — in that order. Compare premium last.
A $0 premium and a $9,250 exposure can sit on the same plan. That combination is legal, common, and the single biggest reason retirees misjudge what a Medicare Advantage plan will cost them. CMS caps the 2026 in-network out-of-pocket limit at $9,250, yet KFF’s June 2026 analysis of CMS benefit files puts the enrollment-weighted average at $5,421 — meaning the difference between two zero-premium plans sitting side by side on Medicare Plan Finder can exceed $4,000 in a bad health year.
Insurers know premium is the number shoppers anchor on. UnitedHealthcare, Humana, Aetna, and Kaiser Permanente all field zero-premium products in most markets, funded by the rebate dollars CMS pays them — $2,664 per enrollee above estimated costs in 2026, per MedPAC. That subsidy buys the $0 headline. It does not buy uniform cost sharing.
This article breaks down the four variables that actually determine your annual spend: the out-of-pocket limit, per-service cost sharing, drug tier placement, and prior authorization scope. Each section shows the arithmetic with 2026 figures verified against CMS and MedPAC.
What the 2026 Numbers Actually Look Like
Start with the ceiling, because it bounds everything else. Federal regulation has required Advantage plans to cap Part A and Part B cost sharing since 2011 — a protection Original Medicare without supplemental coverage does not offer at all. But the cap is a range, not a number.
Sources: KFF analysis of CMS Medicare Advantage Benefit and Landscape files, 2026 (KFF, June 2026); Centers for Medicare & Medicaid Services, 2026 Parts A & B Premiums and Deductibles Fact Sheet (CMS, November 2025).
Two things stand out. The Part D out-of-pocket threshold of $2,100 sits entirely outside the medical out-of-pocket limit — a detail that surprises people who assume one cap covers everything. And the $9,250 ceiling actually fell $100 from the 2025 level of $9,350, the first decline in recent years.
How a Zero-Premium Plan Charges You Anyway
Consider Margaret, 71, in a $0-premium HMO with a $4,600 in-network out-of-pocket limit. She fractures a hip in March. Three-day inpatient admission at $395 per day, ambulance at $300, 14 days in a skilled nursing facility at $196 per day after the first 20 covered days, then eight outpatient physical therapy visits at $40 each.
Her math: $1,185 inpatient + $300 ambulance + $2,744 skilled nursing + $320 therapy = $4,549. She lands $51 short of her out-of-pocket limit, having paid $0 in plan premium all year. Add the $202.90 monthly Part B premium she pays regardless, and her total 2026 outlay is roughly $6,984.
Now shift her to a $28-per-month PPO with a $3,400 out-of-pocket limit and lower per-day inpatient cost sharing. Her supplemental premium cost rises $336 for the year, but her cost-sharing exposure drops by more than $1,100. The higher-premium plan wins by roughly $800 in this scenario — and by considerably more if she is hospitalized twice.
The structure matters more than the headline because Advantage cost sharing is per-service and front-loaded. Unlike the Part A deductible and benefit period structure in Original Medicare, where a single $1,736 deductible covers the first 60 days of a benefit period, Advantage plans typically bill a daily copay for the first several days of each admission. Two short admissions can cost more under Advantage than one long one costs under Original Medicare.
HMO vs PPO: Which Structure Is Cheaper for a Retiree Who Travels?
Network design is the second-largest cost variable after the out-of-pocket limit, and it splits cleanly by plan type. In 2026, 61% of individual MA-PD enrollees are in HMOs and 38% are in local PPOs, per KFF.
Source: KFF analysis of CMS Medicare Advantage Benefit and Landscape files, 2026 (KFF, June 2026).
The premium gap is $72 a year. The out-of-pocket limit gap averages $1,956. On averages alone, the HMO looks cheaper — and for someone who sees the same three doctors in one metro area, it usually is. HMO enrollees are generally responsible for 100% of out-of-network costs, and a Point-of-Service rider does not change that for most services.
For a retiree who spends four months a year in another state, the calculus inverts. An HMO enrollee who needs a specialist while away pays the full billed charge with no cap protection whatsoever, because unlimited out-of-network exposure is not bounded by any out-of-pocket limit. Roughly 46% of HMO enrollment now sits in HMO-POS plans, which permit some specified out-of-network services — but only the ones the plan names.
Verdict
For a geographically stable retiree with an established local care team, the HMO wins: the $1,956 average out-of-pocket limit advantage dwarfs the $72 annual premium difference. For anyone who splits time between states, maintains out-of-area specialists, or expects to relocate within three years, the PPO is the cheaper plan despite worse averages — because a single uncovered out-of-network hospitalization can exceed the entire PPO premium differential by a factor of fifty. Snowbirds and frequent travelers should treat the HMO’s lower out-of-pocket limit as unavailable to them.
Prior Authorization Is a Cost Variable, Not an Inconvenience
Nearly every Advantage enrollee — 99% in 2026 — is in a plan requiring prior authorization for at least some services, according to KFF’s analysis of CMS benefit files. Traditional Medicare rarely requires it.
Where it bites is predictable, because plans concentrate the requirement on expensive services: acute inpatient stays (97% of enrollees), psychiatric inpatient (93%), skilled nursing facility stays (95%), Part B drugs (94%), and home health (90%). Preventive services barely register at 6%.
Scale explains why this belongs in a cost comparison. Advantage insurers processed nearly 53 million prior authorization determinations in 2024 and denied 4.1 million of them — close to 8%. A denied skilled nursing authorization does not mean the care is free; it means the enrollee pays privately, appeals, or goes without. Nursing facility rates commonly run $300 to $400 per day, so a denied 20-day stay converts into a five-figure private bill that never touches the out-of-pocket limit.
When you compare two plans, request each one’s prior authorization list for the services you are most likely to use. Someone managing diabetes and heart failure should weigh this heavily — see our analysis of Advantage versus Original Medicare for chronic conditions for the utilization patterns that make authorization friction expensive.
What Most People Get Wrong When Comparing Plans
Five errors account for most of the money lost in plan selection.
Mistake 1: Treating the Part B rebate as meaningful savings
The “money back in your Social Security check” pitch describes a Part B premium reduction. Among the 6.7 million individual-plan enrollees whose plans offer one, 39% receive under $10 a month — $120 a year against an out-of-pocket limit that can run $9,250. Correct action: treat any rebate under $50 a month as a rounding error and compare out-of-pocket limits instead. Only about 10% of individual-plan enrollees receive $100 or more monthly.
Mistake 2: Assuming the out-of-pocket limit covers drugs
It does not. The medical out-of-pocket limit covers Part A and Part B services only. Part D spending runs against a separate $2,100 threshold in 2026. Someone hitting both caps faces up to $11,350 in a catastrophic year. Correct action: add the two caps together when stress-testing worst-case exposure, and check formulary tier placement for your specific drugs before enrolling.
Mistake 3: Ignoring IRMAA when the plan is chosen
Advantage enrollment does not exempt you from income-related surcharges. A high-income retiree pays IRMAA on both Part B and Part D regardless of plan type, which can dwarf every cost-sharing difference under discussion. Correct action: model your IRMAA surcharge tier first, then compare plans within that constraint.
Mistake 4: Counting dental and vision benefits at face value
More than 99% of individual-plan enrollees have an eye exam or eyeglasses benefit and 98% have a dental benefit — but the scope varies enormously. Many plans cap annual dental payouts and cover preventive cleanings only, leaving crowns and dentures largely uncovered. Correct action: read the annual dollar cap and covered-procedure list, not the benefit name. Our breakdown of dental, vision, and hearing exclusions covers what typically falls outside.
Mistake 5: Enrolling without checking the switch-back path
Leaving Advantage for Original Medicare plus a supplement later can be blocked by medical underwriting in most states after your initial guaranteed-issue window closes. Correct action: verify your state’s rules before enrolling, and understand the annual enrollment switching rules that govern your exit options.
Who Should Choose Advantage — and Who Should Not
Conditional logic beats blanket advice here, because the same plan is a bargain for one household and a liability for another.
Advantage generally wins if: you live and receive care in one metro area; your regular physicians are in-network and you have confirmed this by calling the practices rather than trusting the plan directory; your annual out-of-pocket spending has historically stayed under $3,000; you value bundled dental, vision, and hearing coverage; and you can absorb a $5,000 to $9,250 shock year without financial distress.
Original Medicare with a supplement generally wins if: you have a diagnosed condition requiring specialist care, frequent imaging, or Part B drugs; you travel or maintain two residences; you want provider choice without network constraints; or you place a high value on cost predictability. Medigap Plan G premiums vary widely by state, age, and rating method — industry rate surveys place typical 65-year-old premiums somewhere in the $130 to $250 monthly range, though state-specific 2026 rate data was not available from a primary source at publication. Compare the Plan G versus Plan N cost structures before assuming supplements are unaffordable.
The break-even is arithmetic. Take the annual Medigap premium, subtract the Advantage supplemental premium, and compare that figure against the Advantage plan’s out-of-pocket limit. If a Plan G costs $180 monthly against a $0 Advantage plan, you pay $2,160 in extra premium for certainty. Against an out-of-pocket limit of $5,421, that certainty costs 40 cents per dollar of protected exposure — a reasonable trade for someone with a serious diagnosis and a poor one for someone healthy who rarely uses care.
Federal retirees and people still working past 65 face a different comparison entirely, since coordination with employer coverage and FEHB analysis for federal employees can make Advantage enrollment actively counterproductive.
Frequently Asked Questions
Does a $0 premium Advantage plan really cost nothing?
No. You still pay the standard Part B premium of $202.90 per month in 2026, plus the Part B deductible of $283 and all plan cost sharing up to the out-of-pocket limit. A zero-premium plan means no supplemental premium beyond Part B — nothing more. KFF reports 75% of individual MA-PD enrollees are in such plans in 2026, and their average out-of-pocket limit is $5,421 in-network.
Why do Advantage plans have such different out-of-pocket limits?
CMS sets tiered levels rather than one number. For 2026, plans choose from voluntary, intermediate, and mandatory bands, with the highest mandatory ceiling at $9,250 in-network. Plans electing lower out-of-pocket limits often offset the cost with tighter networks or higher per-service copays, which is why two plans with identical limits can still differ by thousands in real spending.
Does the out-of-pocket limit include my prescription costs?
No. The medical out-of-pocket limit applies only to Part A and Part B services. Part D drug spending accumulates against a separate annual out-of-pocket threshold, set at $2,100 for 2026 under the CMS Part D redesign program instructions. Someone reaching both caps in the same year faces combined exposure of the two amounts added together.
How often do Advantage plans deny prior authorization requests?
Advantage insurers made nearly 53 million prior authorization determinations in 2024 and denied 4.1 million — roughly 8%, per KFF’s analysis of CMS data. Denial rates by service type, plan, and enrollee characteristics are not publicly reported because CMS does not collect that detail. Skilled nursing and post-acute services draw disproportionate scrutiny relative to preventive care.
How We Researched This Article
Every 2026 figure in this article was pulled from primary federal sources or from KFF’s analysis of CMS administrative files, then cross-checked against a second source where one existed.
Premium, deductible, and coinsurance amounts for Parts A and B come from the Centers for Medicare & Medicaid Services fact sheet released November 14, 2025, and the corresponding Federal Register notice on Part B actuarial rates. The Part D out-of-pocket threshold of $2,100 comes from the Final CY 2026 Part D Redesign Program Instructions published by CMS.
Plan-level data — supplemental premiums, out-of-pocket limits by plan type, supplemental benefit availability, prior authorization prevalence, and Part B rebate distribution — comes from KFF’s June 2026 analysis of CMS Medicare Advantage Enrollment, Benefit, and Landscape files. KFF’s figures are enrollment-weighted and exclude employer-group plans, cost plans, PACE plans, and HCPPs; special needs plans are reported separately where noted. Rebate payment figures are drawn from the Medicare Payment Advisory Commission March 2026 report to Congress. Out-of-pocket limits for Medigap Plans K and L were verified against the CMS October 2025 announcement.
The cost scenarios in this article are modeled, not measured. Copay amounts used in the hip fracture example reflect cost-sharing structures commonly filed in 2026 benefit packages but are illustrative; actual copays vary by plan, county, and service. The break-even calculations are original arithmetic applied to verified inputs.
Two limitations deserve emphasis. First, CMS collects data on supplemental benefit utilization but does not release it to researchers or consumers, so no one can currently say what share of enrollees actually uses a dental or transportation benefit. Second, prior authorization denial data is not broken out by service type or plan, which means a plan’s denial behavior for the specific services you need cannot be evaluated in advance from public data. Medigap Plan G premium ranges cited are drawn from industry rate surveys rather than a federal source; state-specific 2026 rate filings were not available from a primary source at publication.
Research last conducted July 2026. All figures were verified against named primary sources before publication.