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5 Costly Medicare Enrollment Mistakes (And How to Avoid Them)

Turning 65 should be a celebration, not a financial nightmare. Yet every year, thousands of Americans make costly Medicare enrollment mistakes that result in permanent penalties, coverage gaps, and unnecessary expenses that can total tens of thousands of dollars over retirement.

At PromiseCare Medical Group, our network of 60+ primary care physicians and 400+ specialists across Riverside County has guided countless patients through Medicare enrollment. We’ve seen firsthand how even small oversights during the Initial Enrollment Period can create lifetime consequences. The good news? Nearly all of these expensive errors are completely preventable with the right information and guidance.

This comprehensive guide reveals the five most financially damaging Medicare enrollment mistakes, backed by our physicians’ decades of combined experience serving the Inland Empire community. Whether you’re approaching your 65th birthday or helping a loved one navigate their Medicare options, understanding these common pitfalls can save you from costly penalties and ensure comprehensive healthcare coverage throughout your retirement years.

Understanding Medicare Basics: A Foundation for Smart Enrollment

Before diving into the costliest mistakes, it’s essential to understand the Medicare landscape. Medicare consists of several parts, each serving specific healthcare needs:

Original Medicare includes Medicare Part A (Hospital Insurance) and Medicare Part B (Medical Insurance). Part A typically comes premium-free if you or your spouse worked and paid Medicare taxes for at least 10 years. Part B requires a monthly premium—$202.90 in 2026 for most beneficiaries—and covers doctor visits, outpatient care, preventive services, and medical equipment.

Medicare Part D provides prescription drug coverage through private insurance companies. While optional, failing to enroll when first eligible can result in a lifetime late enrollment penalty unless you have other creditable coverage.

Medicare Advantage (Part C) offers an alternative to Original Medicare. These plans, offered by private insurers like those accepted at PromiseCare—including Aetna, Alignment Healthcare, Anthem BlueCross, Cigna, Health Net, Humana, Scan Health Plan, and United Healthcare—bundle Parts A, B, and usually D into one comprehensive plan. Most Medicare Advantage plans include additional benefits like dental, vision, and fitness programs not covered by Original Medicare.

Medigap (Medicare Supplement Insurance) works alongside Original Medicare to cover out-of-pocket costs like coinsurance, copayments, and deductibles. Unlike Medicare Advantage, you cannot have both Medigap and Medicare Advantage simultaneously.

Understanding these components helps prevent the enrollment mistakes that can prove most expensive over time.

Mistake #1: Missing Your Initial Enrollment Period

The Cost: Permanent late enrollment penalties that can add hundreds to thousands of dollars to your lifetime Medicare costs.

Why This Mistake Is So Expensive

Your Initial Enrollment Period (IEP) is a seven-month window that begins three months before you turn 65, includes your birthday month, and extends three months after. Missing this critical timeframe triggers permanent penalties that most people pay for the rest of their lives.

For Medicare Part B, the penalty equals 10% of the standard premium for each full 12-month period you could have enrolled but didn’t. If you delay enrollment by three years, for example, you’ll pay 30% more than the standard Part B premium—permanently. Based on 2026 rates, that’s an extra $60.87 per month, or $730.44 per year, every year you have Medicare.

The Medicare Part D late enrollment penalty compounds differently but remains equally permanent. The penalty is calculated by multiplying 1% of the national base beneficiary premium ($38.99 in 2026) by the number of months you delayed enrollment. This amount—rounded to the nearest $0.10—is added to your monthly Part D premium for as long as you have Medicare drug coverage.

Dr. Martinez from PromiseCare’s Hemet location shares a cautionary tale: “We had a patient who assumed Medicare enrollment was automatic at 65. She waited 18 months before realizing her mistake. Now she’s paying an additional 20% on her Part B premium—approximately $40 extra per month—for the rest of her life. Over a 25-year retirement, that’s $12,000 in completely avoidable costs.”

Common Scenarios That Lead to This Mistake

Assumption of Automatic Enrollment: Many people believe Medicare enrollment happens automatically at 65. While this is true if you’re already receiving Social Security benefits at least four months before your 65th birthday, it’s not automatic for everyone. If you’re still working, delay claiming Social Security, or live in Puerto Rico, you must actively enroll.

Working Past 65 Without Understanding Special Rules: If you or your spouse continues working with health insurance from an employer with 20 or more employees, you may qualify to delay Medicare enrollment without penalty. However, this only applies to active employment, not retiree coverage or COBRA continuation coverage. The distinction matters enormously.

Confusing Coverage Types: COBRA, retiree health insurance, and coverage from employers with fewer than 20 employees don’t qualify as exceptions to Medicare enrollment requirements. Many people mistakenly believe these coverage types protect them from late enrollment penalties.

How to Avoid This Mistake

Track Your Enrollment Timeline: Mark your calendar with your Initial Enrollment Period dates. Set reminders starting four months before your 65th birthday to begin researching options. Don’t wait until the last minute—give yourself time to compare plans, understand benefits, and make informed decisions.

Understand Your Work Situation: If you’re working past 65, verify your employer has 20 or more employees and that your health insurance qualifies as an employer group health plan. Contact your HR department and request written confirmation. This documentation proves critical if enrollment questions arise later.

Know Your Special Enrollment Period Rights: When you stop working or lose employer coverage, you have an eight-month Special Enrollment Period (SEP) to enroll in Medicare Part B without penalty. This period begins the month your employment ends or your group health coverage ends, whichever comes first. Don’t confuse this with retiree coverage—once you accept retiree health insurance, your SEP clock may have already started.

Use PromiseCare Resources: Our Medicare enrollment specialists at (951) 390-2840 can help Riverside County residents understand their specific situation. During the Annual Enrollment Period (October 15 – December 7), we offer free educational workshops at our Hemet location and throughout the Inland Empire to help you navigate enrollment decisions.

Verify Social Security Coordination: Contact Social Security Administration at 1-800-772-1213 to confirm your Medicare enrollment status. If you’re not automatically enrolled, they’ll guide you through the application process.

Mistake #2: Choosing Between Medicare Advantage and Original Medicare Without Understanding Long-Term Implications

The Cost: Potentially thousands in additional out-of-pocket expenses annually, restricted access to specialists, and near-impossible switches back to Original Medicare with Medigap later in life.

Why This Decision Requires Careful Consideration

The choice between Medicare Advantage and Original Medicare with Medigap represents one of the most consequential healthcare decisions you’ll make. While both options provide required Medicare coverage, they function completely differently and have dramatically different long-term implications.

Medicare Advantage plans operate through provider networks, similar to HMOs or PPOs. PromiseCare Medical Group participates in-network with major Medicare Advantage plans including Aetna, Alignment Healthcare, Anthem BlueCross, Anthem BlueShield California, Brand New Day, Cigna, Health Net, Humana, Scan Health Plan, and United Healthcare. These plans typically offer low or zero premiums beyond your Part B payment and include extra benefits like dental, vision, and fitness programs.

However, Medicare Advantage plans have tradeoffs:

Original Medicare with Medigap allows you to see any healthcare provider accepting Medicare nationwide. Medigap policies cover most out-of-pocket costs, providing predictable expenses and comprehensive coverage. However, this option requires paying premiums for both your Medigap policy and Medicare Part D drug coverage in addition to Part B premiums.

The Medigap Guaranteed Issue Window Problem

Here’s where many people make a catastrophic mistake: During your Medigap Open Enrollment Period—six months starting the first day of the month you’re 65 and enrolled in Part B—insurance companies must sell you any Medigap policy they offer, regardless of health conditions. They cannot charge more based on preexisting conditions or deny coverage.

Miss this window, and you’re subject to medical underwriting. Insurance companies can reject your application, charge significantly higher premiums, or impose waiting periods for preexisting conditions. Only three states (Connecticut, Massachusetts, and New York) offer year-round guaranteed issue rights.

Dr. Patel from PromiseCare’s Temecula Valley Physicians Medical Group explains: “We’ve seen patients choose Medicare Advantage for the zero premium and extra benefits, planning to switch to Original Medicare with Medigap if they develop serious health issues. By that time, they’re uninsurable for Medigap or face premiums triple what they would have paid at 65. This is a costly mistake we can’t fix later.”

Real Cost Comparisons

Scenario 1: Healthy Individual

For healthy individuals with minimal healthcare needs, Medicare Advantage often costs less annually.

Scenario 2: Chronic Conditions or Serious Illness

For individuals with complex health needs, Original Medicare with Medigap typically provides better value and simpler access to care.

How to Make the Right Choice

Evaluate Your Health Status and Family History: If you have chronic conditions, family history of serious illness, or anticipate needing specialized care, Original Medicare with Medigap may provide better long-term value despite higher upfront premiums.

Consider Your Healthcare Preferences: Do you prefer choosing any doctor nationwide or staying within a local network? How important is prior authorization avoidance? Your answers should guide your decision.

Review Provider Networks Carefully: If considering Medicare Advantage, verify all your current doctors, including specialists, participate in the plan’s network. PromiseCare participates in multiple Medicare Advantage plans, but not every provider in Riverside County does. Our network includes partnerships with Hemet Valley Medical Center, Loma Linda University Medical Center, Southwest Healthcare System, and other major regional hospitals.

Calculate Total Annual Costs: Don’t focus solely on monthly premiums. Add up premiums, copays, coinsurance, and potential out-of-pocket maximums for both options based on your anticipated healthcare usage.

Understand You Can’t Have Both: You cannot combine Medigap with Medicare Advantage. If you have Medigap and want to try Medicare Advantage, you’ll lose your Medigap guaranteed issue rights in most states. Switching back to Medigap later may prove impossible or extremely expensive.

Start With Medigap If Uncertain: If you’re unsure, consider starting with Original Medicare and Medigap during your guaranteed issue window. You can always switch to Medicare Advantage later—but going the other direction becomes much harder.

Consult PromiseCare Physicians: Our care coordination team helps patients understand how different Medicare options work with our services. Schedule a consultation at any of our locations across Hemet, Temecula, Menifee, or Murrieta to discuss your specific healthcare needs and plan compatibility.

Mistake #3: Not Understanding How Employment and Other Coverage Affects Medicare Enrollment

The Cost: Permanent late enrollment penalties, coverage gaps, and potential loss of Health Savings Account (HSA) contribution eligibility.

Why Employment Makes Medicare More Complicated

Continuing to work past 65 creates complex Medicare enrollment scenarios. Making the wrong decision can result in late enrollment penalties even when you thought you were properly covered, or conversely, enrolling unnecessarily and losing valuable benefits like HSA contributions.

The 20-Employee Threshold

Whether your employer has 20 or more employees dramatically affects how Medicare works with employer coverage:

Employers with 20+ employees: Your employer group health plan typically pays primary, and Medicare becomes secondary coverage if you enroll. You can delay Medicare Part B enrollment without penalty as long as you have active employer coverage. When employment ends or coverage terminates, you have an eight-month Special Enrollment Period to enroll.

Employers with fewer than 20 employees: Medicare becomes primary payer even if you have employer coverage. You should typically enroll in Medicare when eligible to avoid coverage gaps. Your employer plan may not pay claims if you don’t have Medicare Part A and Part B.

Dr. Williams from PromiseCare’s Family Senior Medical Group shares: “We had a patient working for a small medical practice with 12 employees. She delayed Medicare enrollment thinking her employer coverage protected her. When she needed surgery at 67, her employer plan denied the claim because Medicare should have been primary. She then faced late enrollment penalties and a coverage gap during a critical health crisis.”

Common Coverage Mistakes

COBRA Isn’t Creditable Coverage for Delaying Enrollment: COBRA continuation coverage from a former employer doesn’t extend your Medicare enrollment window. Once you lose active employer coverage and elect COBRA, your eight-month Special Enrollment Period begins. Waiting until COBRA ends to enroll in Medicare results in late enrollment penalties.

Retiree Coverage Usually Isn’t Creditable: Health insurance from a former employer provided to retirees doesn’t qualify for delayed Medicare enrollment. Most retiree plans require enrolling in Medicare Part A and Part B when eligible and function as secondary coverage. Failing to enroll in Medicare can result in your retiree plan refusing to pay claims.

Spouse’s Coverage Doesn’t Always Protect You: If coverage comes from your spouse’s employer, verify the employer has 20+ employees and that the plan qualifies as an employer group health plan. Some situations that appear to be employer coverage actually don’t qualify for delayed Medicare enrollment.

Union Coverage Varies: Union-sponsored health plans have different rules. Some function like employer group health plans; others don’t. Request written clarification from your union about how Medicare enrollment affects your coverage.

Marketplace Plans Are Never Creditable: If you purchased health insurance through the Affordable Care Act marketplace, you must enroll in Medicare when eligible. Marketplace subsidies end when you become eligible for Medicare Part A, and remaining on marketplace coverage doesn’t protect against late enrollment penalties.

The Health Savings Account Dilemma

If you contribute to a Health Savings Account (HSA) through a high-deductible health plan, enrolling in any part of Medicare ends your ability to contribute. This creates a complicated decision for people working past 65.

The Six-Month Retroactive Enrollment Problem: When you enroll in Medicare Part A, coverage can be retroactive up to six months (but not before your 65th birthday). If you contributed to an HSA during those retroactive months, you’ve made excess contributions subject to penalties.

Strategic Planning Options:

How to Navigate Working Past 65

Document Everything: Get written confirmation from your HR department about:

Coordinate with Social Security: If you’re working past 65, don’t automatically apply for Social Security benefits, as this triggers Medicare Part A enrollment. Understand the timing implications for your specific situation.

Plan HSA Strategy: Stop HSA contributions six months before you expect to enroll in Medicare. Consult a tax advisor about your specific situation.

Use Form CMS-L564: When you enroll in Medicare after using employer coverage past 65, complete Form CMS-L564 (Request for Employment Information) with your employer. This document proves you had qualifying employer coverage and helps prevent wrongful late enrollment penalties.

Understand Your Special Enrollment Period: Your eight-month SEP begins the month your active employment ends OR the month your employer group health coverage ends, whichever happens first. Don’t confuse your last day of work with when coverage actually terminates.

Schedule Pre-Enrollment Consultation: PromiseCare’s care coordination team can help you understand how different enrollment scenarios affect your access to our network of 60+ primary care physicians and 400+ specialists. Call (951) 390-2840 to discuss your situation before your employment ends.

Mistake #4: Automatically Renewing Your Medicare Advantage or Part D Plan Without Annual Review

The Cost: Hundreds to thousands of dollars annually in unnecessary premiums, copays, and drug costs due to plan changes you didn’t notice.

Why Annual Plan Review Is Critical

Medicare Advantage and Medicare Part D plans change every single year. Premiums increase, formularies shift, provider networks adjust, and coverage rules evolve. What was the perfect plan last year may become expensive or inadequate this year.

The Centers for Medicare & Medicaid Services allows plans to automatically renew, meaning you’ll stay in your current plan unless you actively make changes during the Annual Enrollment Period (October 15 – December 7). This convenience becomes costly when you don’t review plan changes annually.

Changes Plans Make Every Year

Formulary Modifications: Your Medicare Part D or Medicare Advantage plan’s formulary—the list of covered prescription drugs—changes annually. Medications covered last year may:

Premium and Cost-Sharing Adjustments: Plans routinely increase monthly premiums, raise deductibles, adjust copays for doctor visits, and modify coinsurance rates for hospital stays and other services.

Provider Network Changes: Medicare Advantage plans add and remove physicians, hospitals, and specialists from networks. Your longtime doctor at PromiseCare might participate in your plan this year but not next year—or vice versa.

Coverage Rules: Plans modify prior authorization requirements, referral procedures, and coverage limitations for durable medical equipment, diagnostic testing, and specialty treatments.

Geographic Service Areas: Some plans expand or contract service areas, potentially affecting coverage if you spend time between multiple locations.

The Annual Notice of Change

Every September, your Medicare Advantage or Part D plan mails an Annual Notice of Change (ANOC) detailing modifications taking effect January 1. This document, often 10-20 pages long, contains critical information most people never read.

Dr. Santos from PromiseCare’s Menifee location notes: “Every January, we see patients surprised their prescriptions aren’t covered anymore or their copays doubled. When we ask if they reviewed their ANOC, most say they threw it away assuming everything stayed the same. That assumption costs them money.”

Real Examples of Costly Auto-Renewal

Case 1: Prescription Coverage Changes
Maria takes medications for diabetes and high blood pressure. Her Part D plan covered both drugs with $10 copays. The next year’s formulary moved her diabetes medication to Tier 4, increasing her copay to $75 per month—an extra $780 annually. A different plan still offered her medications on Tier 2 with $15 copays, but she didn’t compare options during the Annual Enrollment Period.

Case 2: Provider Network Modifications
James’s Medicare Advantage plan included his cardiologist, primary care physician at PromiseCare, and preferred hospital. The following year, his cardiologist’s practice left the network. Rather than finding a new cardiologist in-network, James continued seeing his doctor and paid out-of-network charges—$4,200 more than he would have spent in-network or by switching to a plan that included his specialist.

Case 3: Premium Increases
Patricia’s Medicare Advantage plan had a $0 premium her first year. Without reviewing changes, she auto-renewed. The second year, her premium increased to $35 per month. The third year, $58 monthly. Over three years, she paid $1,458 in premiums while comparable zero-premium plans offered similar benefits. She could have switched to a new plan during any Annual Enrollment Period.

How to Properly Review Your Medicare Coverage

Read Your Annual Notice of Change: Don’t discard this document. Review every section carefully, paying particular attention to:

Check Drug Coverage: Visit the Medicare Plan Finder at medicare.gov and enter all your current medications. Compare how your existing plan covers them versus other available options. Include dosages—coverage sometimes differs based on dose.

Verify Provider Networks: Confirm all your current healthcare providers remain in-network for the coming year. This includes your primary care physician at PromiseCare, specialists, preferred hospitals, and any other providers you see regularly.

Compare Plan Costs: Don’t just look at monthly premiums. Calculate total annual costs including:

Attend PromiseCare Educational Workshops: During the Annual Enrollment Period, PromiseCare hosts free workshops throughout Riverside County. Our team reviews plan changes, helps patients understand their options, and provides resources for comparing plans. Check our website or call (951) 390-2840 for workshop schedules.

Use the Medicare Plan Finder: This free online tool at medicare.gov allows you to:

Consider New Options: Don’t limit yourself to renewing your existing plan or choosing from the same insurance company. New plans enter the market, existing plans improve benefits, and what worked last year may not be your best choice this year.

Review Star Ratings: Medicare rates plans on a five-star scale based on quality and performance. Higher-rated plans typically provide better customer service, easier access to care, and stronger benefits. Plans with five-star ratings offer a Special Enrollment Period allowing you to switch to them any time during the year.

Schedule Annual Medicare Review: Make reviewing your Medicare coverage an annual ritual. Set a reminder for October 1 to begin reviewing your ANOC and researching alternatives. Give yourself time to make informed decisions rather than rushing during the last week of the Annual Enrollment Period.

Mistake #5: Not Coordinating Medicare Enrollment With Other Healthcare Programs and Benefits

The Cost: Loss of valuable benefits, uncoordinated care, missed cost-saving programs, and confusion about coverage during critical health situations.

Why Coordination Matters

Medicare doesn’t exist in isolation. How you enroll and which parts you choose affects interactions with other healthcare programs, benefit eligibility, and cost-assistance options. Failing to coordinate properly can result in losing benefits you’ve already paid for or missing programs that could save thousands annually.

Medicare and Health Savings Accounts

If you contribute to a Health Savings Account through a high-deductible health plan, enrolling in Medicare Part A or Part B ends your HSA contribution eligibility. This creates complications many people don’t anticipate.

The Problem: When you apply for Social Security benefits, you’re automatically enrolled in Medicare Part A. This enrollment can be retroactive up to six months (but not before your 65th birthday). If you continued contributing to your HSA during those retroactive months, you’ve made excess contributions subject to IRS penalties.

The Solution: Stop HSA contributions at least six months before applying for Social Security or Medicare. If you’re working past 65 and want to continue HSA contributions, delay applying for Social Security benefits to avoid automatic Medicare Part A enrollment. Consult a tax professional about your specific situation and timing.

Medicare Savings Programs

Many Riverside County residents qualify for Medicare Savings Programs (MSPs) that help pay Medicare premiums, deductibles, coinsurance, and copayments. These state-administered programs have income and asset limits but can save qualifying individuals thousands annually.

Program Types:

Income Limits for 2026: These programs serve individuals with monthly incomes up to approximately $1,575 (QMB) to $1,774 (QI), with higher limits for couples. Asset limits apply but are relatively generous.

How to Apply: Contact Riverside County’s Health Services Agency or call 1-800-434-0222 to reach California’s Health Insurance Counseling and Advocacy Program (HICAP) for application assistance.

Extra Help for Prescription Drug Costs

The Extra Help program (also called the Low Income Subsidy) helps pay Medicare Part D prescription drug costs. Qualifying beneficiaries save an average of $5,000 annually on prescriptions.

Who Qualifies: Individuals with limited income and resources may qualify for full or partial Extra Help benefits. Income and asset limits change annually and are more generous than many people expect.

Benefits Include:

How to Apply: Apply online at socialsecurity.gov/extrahelp, call Social Security at 1-800-772-1213, or visit your local Social Security office. HICAP counselors can also assist with applications.

Medicare and Medicaid Dual Eligibility

Some individuals qualify for both Medicare and Medicaid (called Medi-Cal in California). Dual eligible beneficiaries receive coordinated benefits from both programs with enhanced coverage and minimal out-of-pocket costs.

Coordination of Benefits: For dual eligible individuals, Medicare pays first for covered services, and Medicaid covers additional costs including Medicare premiums, deductibles, and services Medicare doesn’t cover.

Special Dual Eligible Plans: Some Medicare Advantage plans specialize in serving dual eligible beneficiaries with benefits designed to coordinate Medicare and Medicaid coverage. PromiseCare participates with several plans offering these enhanced benefits.

Veteran Affairs (VA) Benefits and Medicare

Veterans with VA healthcare benefits face unique Medicare coordination challenges. VA benefits and Medicare don’t coordinate directly—they’re separate programs.

Key Considerations:

Strategic Use: Many veterans use VA for medications and routine care while using Medicare for specialist visits, hospitalizations, or services with long VA wait times. PromiseCare physicians work with veterans to coordinate care between systems.

Medicare Coordination with PromiseCare Programs

PromiseCare Medical Group offers specialized wellness and disease management programs that work in conjunction with Medicare benefits:

Heart Health Program: Our comprehensive cardiovascular care program helps Medicare beneficiaries manage heart disease, hypertension, and related conditions. The program coordinates with Medicare-covered preventive services and cardiac rehabilitation benefits.

Diabetes/Pre-Diabetes Self Management Program: This structured program teaches disease management skills while maximizing Medicare’s diabetes prevention and treatment benefits, including diabetes self-management training, medical nutrition therapy, and diabetic supplies coverage.

Weight to Go Program: Our weight management program complements Medicare coverage for obesity screening, counseling, and in some cases, bariatric surgery for qualifying beneficiaries.

Nutrition for Life Program: This preventive nutrition program aligns with Medicare’s annual wellness visit benefits and medical nutrition therapy coverage for chronic conditions.

These programs demonstrate how Medicare benefits work best when coordinated with comprehensive primary care and preventive services.

How to Ensure Proper Coordination

Inventory All Current Coverage: Before enrolling in Medicare, list all health insurance and benefits you currently have:

Contact Each Program: Call or meet with representatives from each program to understand how Medicare enrollment affects your benefits and what coordination rules apply.

Document Everything: Request written confirmation of how Medicare affects other benefits, what coverage continues, and what requirements you must meet. Keep these documents with your Medicare paperwork.

Schedule a PromiseCare Consultation: Our care coordination team understands how Medicare works with our programs and services. We can help you understand what’s covered, coordinate your care across programs, and maximize benefits. Call (951) 390-2840 to schedule a consultation at any of our Riverside County locations.

Use Professional Help: Consider working with a SHIP counselor (State Health Insurance Assistance Program) for personalized guidance coordinating Medicare with other benefits. California’s HICAP provides free, unbiased counseling. Call 1-800-434-0222 to find your local office.

Review Annually: Coordination needs change as programs evolve, your health status changes, and benefits are modified. Review how all your healthcare programs work together each year during the Annual Enrollment Period.

Taking Action: Your Medicare Enrollment Success Plan

Avoiding these five costly Medicare enrollment mistakes requires planning, research, and ongoing attention. Here’s your action plan:

Three Months Before Age 65

Initial Enrollment Period (Three Months Before to Three Months After Your 65th Birthday)

Annually During Open Enrollment (October 15 – December 7)

Year-Round Best Practices

PromiseCare’s Commitment to Medicare Patients

As Riverside County’s longest continually serving Independent Physician Association network, PromiseCare Medical Group has guided thousands of patients through Medicare enrollment and ongoing healthcare management. Our network of 60+ primary care physicians, 400+ specialists, and 18 urgent care centers across the Inland Empire provides comprehensive care coordinated to maximize your Medicare benefits.

We Accept Major Medicare Advantage Plans:

We also welcome patients with Original Medicare seeking coordinated care from dedicated primary care physicians who serve as long-term health advocates.

Medicare Support Services:

Frequently Asked Questions About Medicare Enrollment

Q: When should I enroll in Medicare if I’m still working at 65?

A: It depends on your employer size and coverage type. If your employer (or your spouse’s employer) has 20 or more employees and provides active group health coverage, you can typically delay Medicare Part B enrollment without penalty. Your eight-month Special Enrollment Period begins when you stop working or lose coverage. However, if your employer has fewer than 20 employees, Medicare usually becomes primary and you should enroll when eligible. Always verify your specific situation with your HR department and get written documentation.

Q: Can I switch from Medicare Advantage back to Original Medicare?

A: Yes, you can switch during the Annual Enrollment Period (October 15 – December 7) or Medicare Advantage Open Enrollment Period (January 1 – March 31). However, getting a Medigap policy after your initial guaranteed issue period (first six months with Medicare Part B at age 65) may be difficult. Insurance companies can reject you, charge higher premiums based on health status, or impose waiting periods for preexisting conditions in most states. Plan this transition carefully and consider working with a licensed insurance agent or SHIP counselor.

Q: What happens if I miss my Medicare enrollment deadline?

A: Missing your Initial Enrollment Period typically results in late enrollment penalties and delayed coverage. You’ll need to wait until the General Enrollment Period (January 1 – March 31) to enroll, with coverage starting July 1. Late enrollment penalties for Part B and Part D continue for as long as you have those parts of Medicare. The penalty amounts depend on how long you delayed enrollment. You may avoid penalties if you qualify for a Special Enrollment Period based on employer coverage or other circumstances.

Q: How do I find out which Medicare plan is best for me?

A: Start by assessing your healthcare needs: current medications, preferred doctors and hospitals, anticipated medical services, and budget for healthcare expenses. Use Medicare’s Plan Finder tool at medicare.gov to compare all available options in your area. Consider attending PromiseCare’s free Medicare educational workshops or scheduling a consultation with our care coordination team. SHIP/HICAP counselors at 1-800-434-0222 provide free, unbiased counseling. Compare total annual costs—not just premiums—for plans you’re considering.

Q: Does PromiseCare accept Original Medicare?

A: Yes, PromiseCare physicians accept both Original Medicare and most Medicare Advantage plans. Our network participates with major Medicare Advantage plans including Aetna, Alignment Healthcare, Anthem BlueCross, Anthem BlueShield California, Brand New Day, Cigna, Health Net, Humana, Scan Health Plan, and United Healthcare. When selecting a primary care physician, verify they participate in your specific plan’s network. Call our enrollment line at (951) 390-2840 for current provider network information.

Q: Will I pay lifetime penalties if I delay Medicare enrollment because I’m working?

A: Not if you properly qualify for delayed enrollment. If you (or your spouse) have active employer group health coverage from an employer with 20 or more employees, you can delay Part B without penalty. When that employment or coverage ends, you have an eight-month Special Enrollment Period to enroll without penalties. The key is having qualifying employer coverage and enrolling during your Special Enrollment Period—not waiting until the next General Enrollment Period. Document your employer coverage with Form CMS-L564 when you do enroll.

Q: Can I use Health Savings Account money to pay Medicare premiums?

A: Yes, HSA funds can be used tax-free to pay Medicare Part B, Part D, and Medicare Advantage premiums (but generally not Medigap premiums). However, you cannot contribute new money to an HSA once you enroll in any part of Medicare. If you’re working past 65, carefully plan the timing of Medicare enrollment to avoid excess HSA contribution penalties from retroactive Medicare Part A enrollment.

Q: What’s the difference between the Annual Enrollment Period and Open Enrollment Period?

A: The Annual Enrollment Period (October 15 – December 7) is when anyone with Medicare can make changes to Medicare Advantage and Part D plans for the following year. The Medicare Advantage Open Enrollment Period (January 1 – March 31) is a second window specifically for people already enrolled in Medicare Advantage to switch to a different Medicare Advantage plan or return to Original Medicare. These are separate from your Initial Enrollment Period, which is your first opportunity to enroll in Medicare around your 65th birthday.

Q: Should I get Medigap or Medicare Advantage if I want to see PromiseCare doctors?

A: Both options allow you to see PromiseCare physicians, but they work differently. With Original Medicare and Medigap, you can see any PromiseCare doctor who accepts Medicare assignment. With Medicare Advantage, verify the specific plan’s network includes your preferred PromiseCare providers. Most major Medicare Advantage plans in Riverside County include PromiseCare in their networks, but network participation varies by plan and location. Contact our enrollment team to verify network participation for your specific plan, or compare plan provider directories during your research.

Q: How do I know if I qualify for Extra Help or Medicare Savings Programs?

A: Income and asset limits change annually, but many Riverside County residents qualify without realizing it. For 2026, programs help individuals with monthly incomes under approximately $1,575-$1,774 depending on the specific program. Don’t assume you don’t qualify—many people are surprised they’re eligible. The best approach is to apply or at least have a screening interview. Call Social Security at 1-800-772-1213 for Extra Help information or California HICAP at 1-800-434-0222 for Medicare Savings Programs. Both applications are free and confidential.

Conclusion: Your Medicare Enrollment Success Starts With Information

Medicare enrollment represents one of the most important healthcare decisions you’ll make. The five costly mistakes outlined in this guide—missing your Initial Enrollment Period, choosing the wrong coverage option, misunderstanding employment rules, automatically renewing plans without review, and failing to coordinate benefits—cost Americans tens of thousands of dollars unnecessarily every year.

The good news? Every one of these mistakes is completely avoidable with proper planning, research, and guidance.

At PromiseCare Medical Group, our mission extends beyond treating illness to promoting wellness and preventing problems before they start. That philosophy applies to Medicare enrollment as much as it does to managing chronic conditions or preventing disease. We want Riverside County residents to maximize their Medicare benefits, minimize their costs, and receive the comprehensive healthcare they deserve throughout retirement.

Take action today:

Your retirement healthcare should provide peace of mind, not financial stress. By avoiding these costly Medicare enrollment mistakes, you can focus on what matters most: staying healthy, enjoying life, and thriving throughout your retirement years.

For personalized guidance about Medicare enrollment and how to maximize your benefits through PromiseCare’s network of physicians and specialists, call our enrollment team at (951) 390-2840 or visit any of our locations throughout Riverside County in Hemet, Temecula, Menifee, and Murrieta.

Additional Resources

Medicare Official Resources:

California State Resources:

PromiseCare Resources:

Medical Disclaimer

This information is provided for educational purposes only and should not be considered as medical, financial, or legal advice. Medicare rules, premiums, income thresholds, and program details change annually. Always verify current information through official Medicare sources, consult with qualified professionals, and consider your personal circumstances when making healthcare coverage decisions.

PromiseCare Medical Group physicians can provide guidance about how Medicare coverage works with our services, but we cannot provide insurance advice or enrollment assistance beyond general education. For enrollment questions, contact Medicare directly, work with a licensed insurance agent, or consult with a SHIP/HICAP counselor.

Individual results, costs, and experiences with Medicare plans vary based on health status, location, plan selection, and other factors. The examples provided represent typical scenarios but may not reflect your specific situation.

Medical Consultation Required: Medicare enrollment decisions should be made in consultation with your healthcare providers who understand your specific medical needs, current conditions, and anticipated healthcare requirements. Schedule a consultation with your PromiseCare primary care physician to discuss how different Medicare options align with your healthcare plan.

PromiseCare Medical Group serves Riverside County with a network of 60+ primary care physicians, 400+ specialists, and comprehensive services including preventive medicine, chronic disease management, and urgent care. Our commitment to patient-centered care extends to helping our community navigate complex healthcare decisions like Medicare enrollment. For more information about our services or to find a provider, visit promisecare.com or call (951) 390-2840.

PromiseCare is not affiliated with or endorsed by the U.S. government or the federal Medicare program.