Plan G vs Part D
Medigap Plan G and Part D drug plan (standalone) solve the same problem in different ways. Medigap Plan G is a standardized supplement that works with Original Medicare to cover most Part A and B cost-sharing, typically leaving the Part B deductible as your main residual cost in current designs for new beneficiaries. By contrast, Standalone Part D plans cover outpatient prescriptions for beneficiaries on Original Medicare. The right plan is the one that covers your drugs at the lowest total annual cost at your pharmacies. Below we compare them on cost, coverage, eligibility, and who each one fits best — with sources you can check.
| Factor | Plan G | Part D |
|---|---|---|
| Typical monthly cost | Approx. $100-$250/mo depending on age, state, and tobacco status | Approx. $0-$100+/mo before Extra Help |
| Relative cost | $$$ | $·· |
| Category | Medicare option | Medicare option |
| Is it insurance? | Yes | Yes |
| ACA-compliant major medical | No | No |
| Covers pre-existing conditions | Varies | Varies |
| Eligibility | Guaranteed issue during Medigap open enrollment in most cases. | Medicare enrollment rules apply. |
| Best for | Travelers wanting nationwide access; People who want predictable costs | Original Medicare beneficiaries; Anyone comparing drug-only costs |
Plan G
Medigap Plan G is a standardized supplement that works with Original Medicare to cover most Part A and B cost-sharing, typically leaving the Part B deductible as your main residual cost in current designs for new beneficiaries.
Pros
- Predictable coverage
- Nationwide Medicare access
- Standardized benefits
Cons
- Higher premium than many Advantage plans
- No extras like dental/vision built in
- Underwriting may apply outside OE
Part D
Standalone Part D plans cover outpatient prescriptions for beneficiaries on Original Medicare. The right plan is the one that covers your drugs at the lowest total annual cost at your pharmacies.
Pros
- Drug-focused shopping
- Can change yearly
- Extra Help may lower costs
Cons
- Formulary changes
- Pharmacy networks
- Separate from medical coverage
Frequently asked questions
- Is Plan G or Part D cheaper?
- Part D typically has the lower monthly cost (approx. $0-$100+/mo before extra help), while Plan G runs higher (approx. $100-$250/mo depending on age, state, and tobacco status). The cheaper option is not automatically better — weigh the coverage trade-offs below.
- What is the main difference between Plan G and Part D?
- Popular Medigap letter covering most Original Medicare cost-sharing. Standalone prescription coverage paired with Original Medicare or Medigap.
- Can I switch between Plan G and Part D?
- Often yes, though timing rules apply. Comprehensive insurance changes usually happen during Open Enrollment or a Special Enrollment Period, so check the enrollment window before you switch.
Sources
- Medicare.gov — the official U.S. government Medicare site · reviewed 2026-01-15
- OLYRON HealthMatch editorial methodology — how we source and rate options · reviewed 2026-01-15
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