What is Annual Enrollment Period and Why It Matters
Every year, Medicare gives you a specific window to enroll, switch, or drop health plans. That's Annual Enrollment Period, or AEP. For 2026-2027, AEP runs from October 15 through December 7, 2026. Any changes you make during this period take effect on January 1, 2027.
Think of AEP as your annual healthcare reset. Your current plan might be changing, your needs might be changing, or new plans might be coming to your area. During these eight weeks, you have the power to shop around and choose what works best for you.
What Can You Do During AEP?
During Annual Enrollment Period, you can:
- Join a Medicare Advantage plan (Part C) if you're not already enrolled
- Switch from one Medicare Advantage plan to another
- Drop Medicare Advantage and go back to Original Medicare with Medigap
- Enroll in a standalone Part D prescription drug plan if you're on Original Medicare
- Switch Part D plans or drop your current plan
- Enroll in a Medigap policy (depending on your situation)
What you can't do during AEP: Unless you have a qualifying life event, you can't enroll in Original Medicare or switch from Medigap to Medicare Advantage outside of your Initial Enrollment Period. These rules are stricter and exist to keep the programs stable.
Major CMS Changes Coming for 2027
The Centers for Medicare & Medicaid Services (CMS) has announced several important changes that will affect your health insurance next year:
The $2,000 Out-of-Pocket Maximum Continues
Thanks to the Inflation Reduction Act, the Medicare Part D out-of-pocket spending cap stays at $2,000 in 2027. This is huge. It means that even if you have expensive prescriptions, your out-of-pocket costs are capped. Last year, seniors were hitting $7,000+ before the cap applied. Now it's $2,000. This continues through 2025 and beyond, providing real relief for people taking multiple medications.
Premium Pressures
While we don't know exact premium changes yet (they typically come out in September), expect some plans to adjust rates modestly. Some plans may increase premiums slightly, while others might lower them or stay flat. This is why shopping during AEP is so important—your current plan might not be the lowest-cost option in 2027.
Expanded Supplemental Benefits in Medicare Advantage
More Medicare Advantage plans are adding supplemental benefits like dental, vision, hearing, fitness programs, meal delivery, and transportation services. If you're in a plan that's a bit stripped-down, a new plan entering your market might offer richer benefits. This is especially true in California's urban areas.
What's New in California for 2027
California is one of the nation's most competitive Medicare markets. Here's what's happening:
New Plan Entries and Exits
Every year, some insurers launch new Medicare Advantage plans to serve California seniors, while others might exit certain counties or products. A new plan entering your area could mean fresh options, maybe with better benefits or lower premiums. Conversely, if your current plan is exiting, you'll need to shop for a replacement.
County-Level Availability Shifts
Plan availability in California can vary dramatically by county. Urban areas like Los Angeles, San Francisco, and San Diego typically have 40+ plan choices, while rural counties might have 10-15. Make sure you check what's actually available in your zip code—don't assume plans you've seen ads for are available where you live.
HMO vs. PPO Availability
California has strong availability of both HMO and PPO Medicare Advantage plans, which gives seniors real choice. HMOs typically have lower premiums but require you to use in-network doctors. PPOs are pricier but more flexible. Know what you prefer and check what's available to you.
Your Annual Notice of Change: Read It (Really)
Starting in September, your current health plan will mail you a document called the Annual Notice of Change. This isn't marketing fluff—it contains real information about how your plan is changing for 2027.
Look for:
- Premium changes (going up or down?)
- Deductible and out-of-pocket maximum changes
- Changes to your network of doctors and hospitals
- Formulary changes (what drugs are covered and at what tier)
- Changes to copays and coinsurance
- Any new or dropped supplemental benefits
If your doctor is being dropped from the network, or your favorite drug is moving to a higher tier, you'll want to know about it before AEP ends. This is often the trigger to shop for a different plan.
How to Compare Plans During AEP
Use Medicare Plan Finder
Go to Medicare.gov/plan-compare (or call 1-800-MEDICARE). Enter your zip code, the drugs you take, the doctors you see, and the plan comparison tool will show you every option available to you. You can compare:
- Premium costs
- Deductibles and out-of-pocket maximums
- Whether your doctors are in-network
- Drug coverage and your estimated yearly costs
- Ratings and reviews from other seniors
This tool is free, unbiased, and government-run. It's your best friend during AEP.
Work with a Licensed Agent
If you find the comparison overwhelming, a licensed Medicare insurance agent can help. Good agents (like our team) know the plans deeply, understand California's market, and can walk you through pros and cons side by side. The best part: it costs you nothing. Plans pay agents a commission, but that doesn't come out of your pocket.
Key Deadlines You Need to Know
- October 15 - December 7, 2026: Annual Enrollment Period. Make your plan choice during this window.
- December 7, 2026 at 11:59 PM: AEP deadline. Any changes made by this time take effect January 1, 2027.
- January 1, 2027: Your new plan (or your current plan with changes) takes effect.
- January 1 - March 31, 2027: Medicare Advantage Open Enrollment Period (MA-OEP). If you were enrolled in a Medicare Advantage plan on January 1, 2027, you can switch to Original Medicare during this period. This is your only other chance to leave MA if you miss AEP.
What If You Miss AEP?
Life happens. Maybe you forgot, or you didn't realize you needed to make a choice. If you miss the AEP deadline on December 7:
If you're already enrolled in a Medicare Advantage plan, you get a second chance. From January 1 - March 31, 2027, you can switch to Original Medicare (or to another MA plan if you want) during Medicare Advantage Open Enrollment Period (MA-OEP). After that window closes, you're locked into your plan until next year's AEP, unless you have a qualifying life event (move, loss of employer coverage, etc.).
If you're on Original Medicare and miss AEP, you can't switch plans until next year unless you have that qualifying event. This is why AEP is so important—it's your guaranteed window.
Our Recommendation: Start Shopping Now
Here's our honest advice: Don't wait until November 20th to start thinking about this. Start in mid-October when AEP opens. Spend an afternoon with Medicare Plan Finder, make a list of your top 3-5 options, then give yourself a week to think about it. If you want to talk through options with a real person, reach out to a licensed agent before things get crazy.
The difference between staying with your current plan and switching to a better option can be $50-$200+ per month. For a senior on a fixed income, that's real money. AEP is the time to make sure you're not overpaying.
Final Thoughts
Annual Enrollment Period can feel overwhelming, but it's also an opportunity. Every year, you get a chance to reset your healthcare to match your actual needs and budget. California offers incredible plan choices—use that to your advantage. Read your notices, shop early, and don't hesitate to ask for help.