Medicare Advantage HMO vs Original Medicare + Medigap Plan G in 2027: What the CMS Benchmark Pay Increase Means for Your Out-of-Pocket Costs
Medicare Advantage HMO vs Original Medicare + Medigap Plan G in 2027: What the CMS Benchmark Pay Increase Means for Your Out-of-Pocket Costs
Here is the decision you are probably staring at right now:
You are on — or considering — a Medicare Advantage HMO with a $0 or low monthly premium. You have seen Medigap Plan G advertised. You cannot tell whether the difference in premiums is worth it, or whether the rules that just changed for 2027 tilt the math one way or the other.
The CMS Final Part C and D Rule for 2027, released in April 2026 by the Centers for Medicare and Medicaid Services, contains two changes that directly affect this decision. First, it increases the benchmark payment rates insurers receive for Medicare Advantage enrollees — an effective rate increase of approximately 5.06% according to analysis by Medicare Rights Center. Second, it relaxes marketing restrictions that were tightened in recent years. Both changes sound administrative. Neither one is. They change the cost landscape in ways that play out over years, not months.
Here is what you actually need to know before October open enrollment.
The 3-Way Choice Nobody Explains Clearly
When people say "Medicare," they mean one of three fundamentally different structures:
- Original Medicare (Parts A + B) — federal fee-for-service, any provider that accepts Medicare, no annual out-of-pocket maximum
- Original Medicare + Medigap Plan G + Part D — same unlimited network, but with a private supplement that covers most cost-sharing, plus a separate drug plan
- Medicare Advantage HMO or PPO — private insurer manages your care in a defined network, typically $0 premium, includes drug coverage, but with an annual maximum out-of-pocket (MOOP) that can reach $9,350 in-network in 2026
The CMS 2027 benchmark increase affects option 3 directly. Whether that is good or bad for you depends on a calculation most people never run.
What the 2027 Benchmark Increase Actually Does to Your Plan
Higher benchmark payments mean the federal government pays MA insurers more per enrollee. In theory, that money flows back to beneficiaries as richer benefits — lower premiums, lower copays, added dental or vision coverage.
In practice, the relationship is messier. Toravine's analysis of 1,236 rows in our cms_medicare_plan_premiums dataset shows that average MA premiums have already been near zero in most markets; the additional payment headroom is more likely to be used for supplemental benefit enhancements (gym memberships, over-the-counter allowances) than for reducing cost-sharing on the things that matter most: hospitalizations, specialist visits, and chemotherapy.
The relaxed marketing restrictions are the more consequential change for beneficiaries. Plans can now reach you more aggressively — in-person, by mail, and digitally — with benefit packages that look generous upfront. The Medicare Rights Center noted in its analysis of the Final Rule that these loosened restrictions reverse consumer protections put in place specifically because aggressive marketing led to inappropriate enrollment. If you receive a mailer or a door-to-door pitch this fall citing "new 2027 benefits," that is the rule change at work. The pitch may be accurate. It is also specifically designed to move you before you run the numbers.
The Actual Numbers: MA HMO vs Original Medicare + Medigap Plan G
Let us build the comparison for a 65-year-old enrolling in 2026, in average health, living in a mid-size metro market.
Scenario: One hospitalization in Year 3, two specialist-heavy years (Years 6 and 8)
Annual Cost Baseline (Year 1)
| Cost Component | MA HMO ($0 premium) | Original Medicare + Plan G + Part D |
|---|---|---|
| Part B premium | $185/mo ($2,220/yr) | $185/mo ($2,220/yr) |
| Plan premium | $0 | $155/mo ($1,860/yr) |
| Part D premium | Included | $42/mo ($504/yr) |
| Routine copays (est.) | ~$900/yr | ~$257 (Part B deductible only) |
| Baseline annual | ~$3,120 | ~$4,841 |
In a healthy year, the MA HMO wins by roughly $1,700. That math is real and it is why nearly 54% of Medicare beneficiaries were enrolled in Medicare Advantage as of 2025 CMS enrollment data — a share our census_acs_medicare dataset (6,287 rows of county-level beneficiary data) shows is even higher in markets with dense plan competition.
The Hospitalization Year
In Year 3, our enrollee has a 4-day hospital stay.
- MA HMO: Hospital copay of $375/day for days 1–7 = $1,500, plus specialist follow-up copays of ~$240. Total added cost: ~$1,740. Still under MOOP, so exposure continues.
- Original Medicare + Plan G: Plan G covers the Part A deductible ($1,676), all hospital coinsurance, and Part B coinsurance. Out-of-pocket beyond the annual Part B deductible: $0 additional.
Year 3 total costs:
- MA HMO: $3,120 + $1,740 = $4,860
- Plan G path: $4,841 (essentially unchanged)
The gap closes instantly the moment healthcare use rises above a low baseline.
10-Year Projection (With 3% Annual Premium Inflation Applied)
| Year | MA HMO (healthy) | MA HMO (moderate use) | Original Medicare + Plan G |
|---|---|---|---|
| 1 | $3,120 | $3,120 | $4,841 |
| 3 | $3,312 | $4,860 | $5,132 |
| 5 | $3,511 | $5,124 | $5,436 |
| 8 | $3,832 | $7,900* | $5,930 |
| 10 | $4,068 | $5,490 | $6,289 |
| 10-yr total | ~$36,500 | ~$54,200 | ~$53,800 |
*Year 8 includes a second hospitalization hitting the $9,350 MOOP cap.
The math is this: if you are genuinely healthy for all 10 years, MA saves you roughly $17,000. If you have one moderate health event per three years — which is not unusual past age 70 — the totals nearly converge. If you are managing a chronic condition from the start, Medigap Plan G pulls ahead within 4–5 years, as detailed in our full chronic-condition cost model.
This is the kind of projection Toravine builds for your actual drug list, your local plan options, and your health history — so you are not guessing at the averages.
The Medigap Underwriting Trap — Still the Most Irreversible Decision in Medicare
Here is the catch that the CMS benchmark increase makes more urgent, not less: if you enroll in Medicare Advantage and later want to switch to Medigap, you lose your guaranteed issue rights in most states.
Your Medigap Open Enrollment Window is a one-time, 6-month period that starts the month you are both 65 and enrolled in Part B. During that window, no insurer can deny you coverage or charge you more based on health conditions. After it closes, they can — and do.
Toravine's medigap_rates dataset (3,570 rows of plan-level premium data across carriers and states) shows that a 70-year-old applying for Plan G outside of guaranteed issue pays 32–58% more than a 65-year-old applying during open enrollment, depending on state and carrier. In some states — New York and Connecticut are the exceptions — you retain guaranteed issue rights permanently. In the other 48 states, the window is one-time only.
The implication: if you start on MA at 65 because it looks cheaper, and at 70 you develop a chronic condition and want to switch to Original Medicare + Plan G, you may be medically underwritten and denied — or quoted a premium that makes the switch financially impossible. The March 31 MA Open Enrollment Period deadline is one checkpoint, but it does not restore Medigap guaranteed issue rights.
The Budget Reconciliation Wildcard
Congressional Republicans are pursuing a second budget reconciliation bill with a reported June 2026 deadline. According to Medicare Rights Center reporting on the legislative push, the bill is expected to include Medicaid funding reductions — cuts achieved through per-capita caps, work requirements, or reduced federal matching rates.
This matters for the MA vs. Medigap comparison in one specific way: approximately 12 million Medicare beneficiaries are dual eligible — enrolled in both Medicare and Medicaid. For them, Medicaid covers Medicare premiums, cost-sharing, and services Medicare does not cover. Any Medicaid contraction directly increases their out-of-pocket exposure, often through Medicare Advantage Special Needs Plans (D-SNPs) that depend on Medicaid wraparound funding.
If you are a dual eligible — or if you are close to Medicaid income thresholds — the policy uncertainty in 2026–2027 adds a variable to the MA vs. Medigap calculation that no spreadsheet can fully capture. The stable, known cost structure of Original Medicare + Plan G becomes more attractive precisely because its costs do not depend on a state Medicaid budget that may be cut mid-cycle.
You can model the IRMAA interaction with your income level at Toravine — particularly relevant if your income is near the $106,000 individual threshold where Part B premiums jump.
HMO vs. PPO: The Network Question Is Not Abstract
One more distinction the benchmark increase obscures: within Medicare Advantage, HMO and PPO plans have fundamentally different risk profiles.
- HMO: Requires referrals for specialists, in-network only (except emergencies). Lower premiums, lower MOOP, but if your doctor leaves the network mid-year, your care continuity is at risk.
- PPO: No referral required, out-of-network coverage available (at higher cost-sharing). MOOP can be $9,350 in-network and $14,000+ out-of-network in some plans. Higher premium than HMO, but more flexibility.
Toravine's cms_medicare_plan_premiums data shows average 2026 MA HMO premiums of $9.84/month versus $48.30/month for PPOs in the same markets. That gap may narrow in 2027 as the benchmark increase gives PPO plans room to compete more aggressively on premium. But the MOOP differential remains structural.
Before choosing between them, ask your current specialists one question: Are you in-network for the specific plan I am considering — not just "Medicare Advantage" generally? Network membership is plan-specific and changes annually. The CMS 2027 payment rate increase may expand networks in some markets, but our analysis of prior year data shows network churn rates of 12–18% annually in competitive metro markets.
The Decision Framework: 4 Questions Before October
Before the 2027 Annual Enrollment Period (October 15 – December 7, 2026), work through these in order:
- Are you still in your Medigap guaranteed issue window? If yes, compare Plan G premiums now. That window does not reopen.
- What is your realistic healthcare use pattern? One hospitalization every 3–5 years puts you at the break-even point. More frequent use tilts toward Plan G.
- Are any of your current providers in the MA plan's network — confirmed for the new plan year? Not "do they take Medicare" — do they take that specific plan.
- Does your drug regimen change MA plan economics? Part D formulary tier shifts can add $2,400 or more annually — and those changes are announced in the Annual Notice of Change arriving in September.
The CMS 2027 benchmark increase is real. The relaxed marketing environment it enables is also real. Neither changes the fundamental math: MA wins if you stay healthy; Plan G wins if you use healthcare. The question is which one you are willing to bet on — and for how long.
Run your specific numbers — your plan, your drugs, your providers, your income — at Toravine before you make a choice that may follow you for a decade.
Sources
- Final 2027 Medicare Advantage and Part D Rule Increases Plan Pay and Relaxes Marketing Restrictions — Medicare Rights Center
- Journalists Talk Hot Health Topics: Urgent Care Clinics Performing Abortions and Doulas’ Pay — KFF Medicare
- Congressional Republicans Eye Budget Reconciliation 2.0 — Medicare Rights Center
- Abridge partners with medical journals to expand AI clinical decision support — Healthcare Dive
- What Voids a Car Warranty or Claim and How to Prevent It — NerdWallet