Reviewed by Anthony Howe, Licensed Insurance Agent, NPN #20649362. Updated October 23, 2026, for 2027 coverage.
Most Medicare decisions in San Diego County come down to one fork in the road: a Medicare Advantage plan, or Original Medicare with a Medicare Supplement (Medigap) plan and a separate Part D drug plan. National articles tend to compare the two in general terms. Here, the answer depends a lot on local details: which medical group your doctors belong to, how often you travel, and what the 2027 plans in this county actually look like.
The two paths in one paragraph each
Medicare Advantage (Part C) is a private plan approved by Medicare that covers everything Original Medicare does, usually includes drug coverage, and often adds dental, vision and hearing benefits. You keep paying your Part B premium. Plans use networks, and you pay copays and coinsurance up to a yearly out-of-pocket maximum.
Original Medicare with Medigap lets you see any doctor or hospital in the country that accepts Medicare, with no network or referrals. A Medigap plan helps pay what Original Medicare leaves to you, such as the Part B coinsurance, and you add a stand-alone Part D plan for prescriptions. You pay more in monthly premiums and much less, or nothing, when you use care. The two don’t combine: Medigap can’t be used with a Medicare Advantage plan.
What the 2027 San Diego County market looks like
From CMS’s 2027 plan data, there are 46 Medicare Advantage plans open to anyone in the county, down from 60 in 2026. Forty-two of them are HMOs or HMO-POS plans, and only four are PPOs. Thirty-two of the 41 plans with drug coverage have a $0 monthly premium, and the median in-network out-of-pocket maximum is about $3,475. Sharp Health Plan isn’t offering Medicare Advantage for 2027. On the Original Medicare side, stand-alone Part D plans in California have a median premium of about $151 a month for 2027, and none has a $0 premium. Our breakdown of the 2027 plan data has the details.
Side by side
| Medicare Advantage | Original Medicare + Medigap + Part D | |
|---|---|---|
| Doctors and hospitals | The plan’s network, often through a medical group | Any provider in the U.S. that accepts Medicare |
| Referrals and prior authorization | Common, especially in HMOs | Generally not needed under Original Medicare |
| Monthly premiums | Often $0 beyond Part B | Part B plus a Medigap premium plus a Part D premium |
| Costs when you use care | Copays and coinsurance up to a yearly maximum | Low or none, depending on the Medigap plan |
| Drug coverage | Usually included | Separate Part D plan |
| Travel | Limited outside the plan’s area, except emergencies | Same coverage anywhere in the U.S. |
| Extra benefits | Dental, vision, hearing and allowances in many plans | Not included; separate policies available |
| Switching later | Can return to Original Medicare during AEP, but Medigap may ask health questions | California’s birthday rule allows yearly Medigap switches |
Where Medicare Advantage tends to fit
- Your doctors are in one medical group that works with the plan, and you’re comfortable getting referrals through your primary care doctor.
- You’d rather keep monthly premiums low and pay copays as you use care, with the out-of-pocket maximum as a ceiling.
- Dental, vision or hearing benefits in one plan matter to you.
- You spend most of the year in San Diego County.
Where Medigap tends to fit
- You see specialists in different medical groups or health systems, or want access to providers outside the county, such as a cancer center elsewhere.
- You travel or split the year between two places.
- You’d rather pay a predictable premium than copays, and avoid prior authorization for most care.
- You’re in your Medigap open enrollment period (the six months after you’re 65 and in Part B), when an insurer can’t turn you down for health reasons.
Local trade-offs we see most
Medical groups decide a lot. Many San Diego Medicare Advantage plans work through medical groups, and your primary care doctor’s group often decides which specialists and hospitals you can use. For 2027, doctors are moving between groups and groups are changing which plans they work with, which is the issue clients bring up most. Two plans from the same insurer can include different groups, so check each doctor by name and by plan.
Wait times. Some clinics are very busy, and long waits for appointments are a common reason people look at a change. With Medicare Advantage, a plan that uses a different medical group can mean a different clinic; with Original Medicare, you can go to any provider who accepts Medicare and has openings.
Prior authorization. Many plans require approval for imaging, procedures and some specialist visits. Starting in 2027, plans can process requests electronically and you may be able to follow them in an online portal, but the requirement itself remains.
Switching back is the fine print. You can leave Medicare Advantage for Original Medicare during the Annual Enrollment Period, but outside your Medigap open enrollment period or a guaranteed-issue situation, a Medigap insurer can usually ask health questions and decline you. California’s birthday rule, which lets you switch Medigap plans for 60 days each year starting on your birthday, helps people who already have Medigap, not people coming from Medicare Advantage. If your Medicare Advantage plan is ending, as Sharp Health Plan’s are for 2027, you do get a guaranteed right to buy certain Medigap plans.
Extra benefits come with rules. Grocery, utility and similar allowances are often limited to members with qualifying chronic conditions; for 2027, plans must publish who qualifies, and benefit cards only work for eligible items within the plan year. See our OTC allowance guide.
A useful order for comparing
- List the doctors, specialists and hospital you want to keep, with their medical groups.
- List every prescription, with strength, and your pharmacy.
- Compare the yearly medical cost and the yearly drug cost separately, including premiums, deductibles and the out-of-pocket maximum.
- Look at extra benefits last, once the core coverage fits.
- If you’re moving from Medicare Advantage to Original Medicare, settle whether a Medigap plan will accept you before you switch.
Where an independent broker helps
You can do every step above yourself with the Medicare Plan Finder, and California’s free HICAP counselors (1-800-434-0222) can help. An independent broker is another option:
- Several insurers in one conversation. A broker who represents more than one company can compare Medicare Advantage, Medigap and Part D plans side by side.
- Your doctors and drugs, checked plan by plan. Including medical groups, formularies, tiers, prior authorization and preferred pharmacies, with an estimate for the whole year.
- Retiree plans. Many people roll into whatever Medicare plan their employer, union or pension system offers. A retiree plan can compare well, especially with an employer subsidy, but it isn’t automatically the option that fits best, and some don’t let you return once you leave. We work with many retiring teachers and public employees on exactly this question.
- A yearly check. Drugs leave formularies, doctors change groups and plans end. Reviewing each fall doesn’t mean you have to switch; it’s how you find out.
- No added cost. Brokers are paid by the insurance companies, and your premium is the same whether you enroll through a broker or directly.
Rock Meadow Insurance Services works with Medicare clients from our Oceanside office and across California. Call (760) 654-6760 to compare your options, or see Medicare in San Diego. For the full 2027 checklist, see our Annual Enrollment Period guide.
