Original Medicare pays 80% of your approved medical costs. That other 20%? It's yours — with no annual cap. Which means a major surgery, prolonged hospital stay, or complicated treatment could leave you with bills that keep climbing with no ceiling. That's not a design flaw — it's exactly why Medicare Supplement plans, called Medigap, exist.
What Does Medigap Cover?
Medigap is private insurance that works alongside Original Medicare. When Medicare pays its 80%, your Medigap plan covers some or all of what's left:
- The Part B 20% coinsurance on doctor visits and outpatient services
- The Part A hospital deductible ($1,736 per benefit period in 2026)
- Part A coinsurance for extended hospital stays
- Skilled nursing facility coinsurance
- Foreign travel emergency coverage (most plans)
What Medigap does not cover: prescription drugs (you need separate Part D), routine dental, vision, or hearing. And it cannot be combined with Medicare Advantage — you use one or the other.
The Freedom Medigap Gives You
With Original Medicare plus Medigap, you can see any doctor or hospital in the country that accepts Medicare. No networks. No referrals. No prior authorization for covered services. This flexibility is particularly valuable for Californians who travel, split time between cities, or have specialists they're unwilling to leave.
Whether you're on Medigap or Medicare Advantage, our California doctor directory helps you verify which physicians accept Medicare before making an appointment.
Search by name, specialty, or city — from Southern California to the Bay Area and beyond.
The Plans You'll Actually Choose Between
Ten standardized Medigap plans exist (A through N). Federal law requires identical benefits within the same plan letter — a Plan G from Company A covers exactly what Plan G from Company B covers. The only differences: monthly premium and customer service.
For most people enrolling in Medicare today, the decision comes down to Plan G vs Plan N:
| Feature | Plan G | Plan N |
|---|---|---|
| Part A Hospital Deductible | Covered | Covered |
| Part B 20% Coinsurance | Covered in full | Covered, except small copays |
| Part B Deductible ($283) | Not covered | Not covered |
| Skilled Nursing Coinsurance | Covered | Covered |
| Foreign Travel Emergency | Covered (80%) | Covered (80%) |
| Doctor Visit Copay | $0 | Up to $20 |
| ER Visit Copay | $0 | Up to $50 (waived if admitted) |
| Typical CA Monthly Premium | $100–$250/mo | $80–$200/mo |
Plan G offers more complete protection. Plan N trades a lower premium for small copays. If you're healthy and rarely see doctors, Plan N often wins mathematically.
The One Window You Cannot Miss
Your Medigap Open Enrollment Period lasts exactly six months
If you're approaching 65, this deadline is as important as any other Medicare enrollment date. Don't let it pass.
How Much Does Medigap Cost in California?
Because benefits are standardized within each plan letter, the only reason to pay more is not knowing your options. Prices vary significantly — the same Plan G can cost $130/month from one insurer and $210/month from another in the same California county.
Pricing factors: age at enrollment, rating method (community-rated, issue-age-rated, or attained-age-rated), county, and the insurer's rate history. Shopping across companies — for identical coverage — is always worth it.
Meet Diane From San Diego
Diane — San Diego, CA
Diane chose Medicare Advantage at 65 for the $0 premium. For seven years it worked fine. Then she developed a chronic condition requiring frequent specialist visits, and her out-of-pocket costs added up quickly.
She called How2Medicare during AEP wanting to switch to Original Medicare plus Medigap. Past her guaranteed window, she had to go through underwriting — eventually approved, but at higher rates than she'd have paid at 65.
The lesson: if you want Medigap long-term, enroll during your guaranteed window. Switching back from Advantage gets harder over time.
Want to compare Medigap plans in your California city?
We'll compare premiums from multiple insurers for identical Plan G and Plan N coverage — because when benefits are the same, the only reason to pay more is not knowing your options.
Book a free callHow2Medicare is a free service of J Johnston Insurance, helping California seniors understand their supplement options and stop overpaying for identical coverage.