Key Takeaways

• Enrolling in Medicare Part C (Medicare Advantage) while also enrolled in a Postal Service Health Benefits (PSHB) plan can lead to overlapping coverage, conflicting rules, and unexpected costs.

• PSHB plans already integrate with Medicare Parts A and B, offering benefits that may be reduced or duplicated by enrolling in a separate Part C plan.

Understanding What Part C Actually Is

Medicare Part C, also known as Medicare Advantage, is a private insurance alternative to Original Medicare. It combines Parts A and B into one bundled plan and often includes prescription drug coverage and other extras like dental or vision. In 2025, these plans continue to attract many Medicare-eligible individuals with their all-in-one structure and marketing of added benefits.

However, unlike Original Medicare, Part C plans follow their own rules for coverage, networks, and cost-sharing. This is where problems can arise if you’re already enrolled in a PSHB plan.

What PSHB Offers to Medicare-Enrolled Postal Retirees

As of 2025, the PSHB program is designed to work in tandem with Original Medicare. If you’re enrolled in Medicare Parts A and B:

• Your PSHB plan acts as secondary payer after Medicare.

• You typically benefit from reduced deductibles and copayments.

• Many PSHB plans offer integrated Medicare Part D prescription drug coverage through an Employer Group Waiver Plan (EGWP).

• Some PSHB plans even reimburse part of your Medicare Part B premium.

This level of coordination is built into the PSHB program and doesn’t require enrolling in Part C.

Why People Consider Adding Part C Anyway

Despite the built-in coordination with Original Medicare, some postal retirees still explore Medicare Advantage plans. Reasons might include:

• Interest in additional benefits like dental, hearing, or gym memberships.

• Perceived lower out-of-pocket costs.

• Marketing emphasis on convenience or extra perks.

While these reasons may sound compelling, they often overlook how PSHB and Part C might not mesh well when used together.

1. Part C Can Override Medicare—And Disrupt PSHB

When you enroll in a Medicare Advantage plan, you’re essentially leaving Original Medicare. That changes how your healthcare is billed:

• Your Part C plan becomes the primary payer, not Medicare.

• Your PSHB plan may now act as a secondary payer to your Part C plan—or may not coordinate at all.

This shift can confuse claims processing, slow down reimbursements, and result in denied payments for services.

2. You’re Paying for Two Plans—But Only Using One

In 2025, PSHB premiums continue for retirees unless you opt out of coverage. If you enroll in Part C, you are:

• Still paying your monthly PSHB premium.

• Still paying your Medicare Part B premium (required for Part C).

• Possibly paying an additional premium for the Part C plan itself.

That means you’re financially committed to both, but only actively using one—the Medicare Advantage plan. The benefits of your PSHB plan may sit unused, yet you continue paying for them.

3. Prescription Drug Coverage Could Clash

Most PSHB plans already include Medicare Part D drug coverage through a group plan. Medicare does not allow you to be enrolled in two Part D plans at the same time.

Because many Part C plans include built-in Part D coverage, enrolling in one can automatically disenroll you from the PSHB drug plan. That may reduce your access to:

• National pharmacy networks available through PSHB drug plans

• Lower negotiated rates for medications

• Employer-backed prescription benefits, such as a $35 cap on insulin or a $2,000 annual out-of-pocket limit

4. PSHB Plans Are Already Enhancing Medicare Coverage

In 2025, PSHB plans are structured to reduce your costs when paired with Medicare. You may already receive:

• Lower deductibles

• Waived or reduced coinsurance

• Access to specialists without referrals

• Coverage that travels with you nationwide

By switching to Part C, you might lose many of those employer-negotiated cost advantages and provider freedom.

5. Network Restrictions Can Be Limiting

Medicare Advantage plans often come with limited provider networks. Depending on the plan, you might be required to:

• Get referrals to see a specialist

• Use only in-network doctors or hospitals

• Pay higher out-of-pocket costs when seeking care outside the network

In contrast, PSHB plans—when paired with Original Medicare—give you access to any provider that accepts Medicare. That flexibility matters, especially if you travel or move.

6. Prior Authorization Requirements May Increase

Many Medicare Advantage plans in 2025 still require prior authorizations for a wide range of services. That means:

• You must get approval before receiving certain treatments, tests, or surgeries.

• Delays or denials could affect your care timeline.

PSHB plans, acting as secondary insurers with Medicare, are less likely to impose these hurdles when Medicare has already approved the service.

7. Your PSHB Plan May Not Reimburse Costs Like Before

If you move to a Part C plan, your PSHB plan is no longer coordinating with Original Medicare. That can change how cost-sharing works:

• Any PSHB premium reimbursement you once received may end.

• You may not get the same level of cost reduction on out-of-pocket medical expenses.

• Your PSHB plan might provide limited or no secondary benefits to your Part C plan.

These shifts can increase your total healthcare costs, especially if you assumed you’d be double-covered.

8. You Risk Losing Certain PSHB Protections

PSHB offers postal retirees protections not found in all Medicare Advantage plans, including:

• Continued FEHB/PSHB eligibility for survivors if survivor benefits are elected.

• Broad nationwide coverage that isn’t tied to one region.

• Stronger oversight and accountability through OPM.

Opting for Part C may shift your coverage outside of these safeguards. That can be a problem if you need to switch back later or face unexpected changes in the plan.

What You Can Do Instead

Rather than enrolling in Part C, you can enhance your PSHB coverage while keeping Medicare Parts A and B. Consider these alternatives:

• Explore PSHB plans that offer added benefits when combined with Medicare, such as dental or vision riders.

• Use Medicare’s preventive services, many of which have no additional cost.

• Take advantage of your PSHB plan’s telehealth, wellness programs, or reimbursement benefits.

These options help you avoid duplicative costs and ensure better coordination of benefits.

Final Thoughts for Postal Retirees

The transition to PSHB in 2025 is built around coordination with Medicare Parts A and B—not Part C. Enrolling in a Medicare Advantage plan on top of your PSHB plan can complicate your coverage, increase costs, and leave you with fewer protections than you expected.

Unless you’re opting out of PSHB entirely, it’s typically not beneficial to add a separate Medicare Advantage plan. If you’re unsure what’s best for you, get in touch with a licensed insurance agent listed on this website. They can review your specific situation and help you compare the pros and cons before you make a move that affects your healthcare security.